FEDERAL COURT OF AUSTRALIA

Boehringer Ingelheim Animal Health USA Inc v Elanco New Zealand [2021] FCA 1457

Appeal from:

Merial, Inc v Bayer New Zealand Limited [2019] APO 21

File number:

VID 581 of 2019

Judgment of:

BESANKO J

Date of judgment:

25 November 2021

Catchwords:

INTELLECTUAL PROPERTY appeal under s 104(7) of Patents Act 1990 (Cth) from orders made by delegate of Commissioner of Patents allowing amendments to Patent Application where respondent filed Patent Application for anti-infective formulation to prevent or ameliorate mammary gland infections including mastitis where application disclosed invention comprising oil-based physical barrier material and at least one antiseptic compound mixed with barrier material where application disclosed that any antiseptic may be used in formulation and disclosed preferred and suitable characteristics and properties of antiseptic where appellant successfully opposed application on grounds of lack of novelty and lack of inventive step where cited prior art disclosed use of acriflavine, an acridine, in teat seal formulation where delegate made finding that part of common general knowledge that acriflavine had antiseptic property where respondent applied for amendments to application including amendments that antiseptic compound mixed with barrier material is not an acridine where appellant opposed amendments on basis that amendments not allowable under s 102(1) and/or ss 102(2)(b) and 40(3) of Patents Act whether matter claimed by specification as a result of amendments travel beyond matter in substance disclosed in specification as filed whether claim of amended specification excluding acridines from use in formulation fundamentally inconsistent with specification as filed appeal dismissed

INTELLECTUAL PROPERTY where specification as filed disclosed use of any antiseptic in formulation and disclosed preferred and suitable characteristics and properties of antiseptic where claim of amended specification excluded acridines from use in formulation whether, properly construed, specification as filed disclosed use of acridines in formulation and/or disclosed that acridines a preferred antiseptic whether characteristics and properties of acridines and their use in veterinary science part of common general knowledge before priority date

INTELLECTUAL PROPERTY where appellant successfully opposed Patent Application where delegate made findings in decision on substantive opposition proceeding as to common general knowledge before priority date where respondent did not appeal from decision on substantive opposition proceeding where respondent applied for amendments to application whether parties bound by findings made in decision on substantive opposition proceeding on appeal from orders made on amendment application

Legislation:

Patents Act 1990 (Cth) ss 40, 102, 104

Cases cited:

Aktiebolaget Hässle v Alphapharm Pty Ltd [1999] FCA 628; (1999) 44 IPR 593

Aktiebolaget Hässle v Alphapharm Pty Ltd [2002] HCA 59; (2002) 212 CLR 411

Alphapharm Pty Ltd v H Lundbeck A/S [2008] FCA 559; (2008) 76 IPR 618

AMP Incorporated v Hellerman, Ltd [1962] 1 All ER 673; [1962] RPC 55

Aspirating IP Ltd v Vision Systems Ltd [2010] FCA 1061; (2010) 88 IPR 52

AstraZeneca AB v Apotex Pty Ltd [2014] FCAFC 99; (2014) 226 FCR 324

Blair v Curran [1939] HCA 23; (1939) 62 CLR 464

British Acoustic Films Ltd v Nettlefold Productions Ltd (1935) 53 RPC 221

CCOM Pty Ltd v Jiejing Pty Ltd [1994] FCA 1168; (1994) 51 FCR 260

Commissioner of Patents v Sherman [2008] FCAFC 182; (2008) 172 FCR 394

DSI Australia (Holdings) Pty Ltd v Garford Pty Ltd [2013] FCA 132; (2013) 100 IPR 19

Emperor Sports Pty Ltd v Commissioner of Patents [2005] FCA 996; (2005) 146 FCR 159

Ethyl Corporation’s Patent [1972] RPC 169

Fina Research SA v Halliburton Energy Services Inc (No 2) [2003] FCA 251; (2003) 127 FCR 561

Gambro Pty Ltd v Fresenius Medical Care South East Asia Pty Ltd [1999] FCA 1848; (1999) 48 IPR 625

Gambro Pty Ltd v Fresenius Medical Care South East Asia Pty Ltd [2000] FCA 1044; (2000) 49 IPR 321

Graham Hart (1971) Pty Ltd v S W Hart & Co Pty Ltd [1978] HCA 61; (1978) 141 CLR 305

ICI Chemicals & Polymers Ltd v Lubrizol Corporation Inc [2000] FCA 1349; (2000) 106 FCR 214

Idenix Pharmaceuticals LLC v Gilead Sciences Pty Ltd [2017] FCAFC 196; (2017) 134 IPR 1

Kaiser Aluminium & Chemical Corporation v Reynolds Metal Co [1969] HCA 7; (1969) 120 CLR 136

Kimberly-Clark Australia Pty Ltd v Arico Trading International Pty Ltd [2001] HCA 8; (2001) 207 CLR 1

Kuligowski v Metrobus [2004] HCA 34; (2004) 220 CLR 363

Lockwood Security Products Pty Ltd v Doric Products Pty Ltd [2004] HCA 58; (2004) 217 CLR 274

Martin Engineering Co v Trison Holdings Pty Ltd [1989] FCA 64; (1989) 14 IPR 330

Meat & Livestock Australia Ltd v Cargill, Inc [2018] FCA 51; (2018) 354 ALR 95

Meat & Livestock Australia Ltd v Cargill, Inc (No 2) [2019] FCA 33; (2019) 139 IPR 47

Merck, Sharpe & Dohme (Australia) Pty Ltd v Genentech Inc [2016] FCA 324; (2016) 118 IPR 498

Merial, Inc v Bayer New Zealand Limited [2017] APO 27

Minnesota Mining and Manufacturing Co v Beiersdorf (Australia) Ltd [1980] HCA 9; (1980) 144 CLR 253

New England Biolabs Inc v F Hoffmann-La Roche AG [2004] FCAFC 213; (2004) 141 FCR 1

Olin Corporation v Super Cartridge Co Pty Ltd [1977] HCA 23; (1977) 180 CLR 236

R v Smith; Ex parte Mole Engineering Pty Ltd [1981] HCA 25; (1981) 147 CLR 340

Ramsay v Pigram [1968] HCA 34; (1968) 118 CLR 271

Ranbaxy Laboratories Ltd v AstraZeneca AB [2013] FCA 368; (2013) 101 IPR 11

RGC Mineral Sands Pty Ltd v Wimmera Industrial Minerals Pty Ltd [1998] FCA 1358; (1998) 89 FCR 458

SNF (Australia) Pty Ltd v Ciba Speciality Chemicals Water Treatments Ltd [2016] APO 8

Société des Usines Chimiques Rhône-Poulenc v Commissioner of Patents [1958] HCA 27; (1958) 100 CLR 5

Technological Resources Pty Ltd v Tettman [2019] FCA 1889; (2019) 375 ALR 185

United States Gypsum Company v CSR Building Products Ltd [2017] FCA 595

Birss C (ed), Terrell on the Law of Patents (19th ed, Sweet & Maxwell, 2020)

Division:

General Division

Registry:

Victoria

National Practice Area:

Intellectual Property

Sub-area:

Patents and associated Statutes

Number of paragraphs:

276

Dates of hearing:

3–4, 79, 11 September 2020

Counsel for the Appellant:

Mr C Dimitriadis SC with Ms C Cunliffe

Solicitor for the Appellant:

Ashurst Australia

Counsel for the Respondent:

Mr E Heerey QC with Mr P Creighton-Selvay

Solicitor for the Respondent:

HWL Ebsworth

ORDERS

VID 581 of 2019

BETWEEN:

BOEHRINGER INGELHEIM ANIMAL HEALTH USA INC

Appellant

AND:

ELANCO NEW ZEALAND

Respondent

order made by:

BESANKO J

DATE OF ORDER:

25 November 2021

THE COURT ORDERS THAT:

1.    The respondent file and serve draft minutes of order reflecting the conclusions in these reasons.

Note:    Entry of orders is dealt with in Rule 39.32 of the Federal Court Rules 2011.

REASONS FOR JUDGMENT

BESANKO J:

Introduction

1    This is an appeal by Boehringer Ingelheim Animal Health USA Inc (Boehringer) under s 104(7) of the Patents Act 1990 (Cth) (the Act) against a decision by a delegate of the Commissioner of Patents (the delegate) to dismiss its opposition to amendments to a Patent Application (Merial, Inc v Bayer New Zealand Limited [2019] APO 21). The opponent before the delegate and the original appellant in the appeal was Merial, Inc, but following a corporate restructure under which Merial, Inc transferred all of its rights and liabilities to Boehringer, Boehringer was substituted as the appellant. The applicant for the amendments and respondent to the appeal when the appeal was instituted was Bayer New Zealand Limited. That company assigned the Patent Application to an unlimited company, Elanco New Zealand (Elanco) and an order was made that Elanco New Zealand be substituted as the respondent to the appeal. There was another party which opposed the proposed amendments, Norbrook Laboratories Limited, and that party brought its own appeal against a separate decision of the same delegate to dismiss the opposition. However, Norbrook Laboratories Limited discontinued its appeal before the hearing in this Court.

2    Although s 104(7) of the Act refers to an “appeal”, the nature of the hearing is not an appeal in the strict sense. It is a proceeding in the original jurisdiction of the Court and is conducted as a rehearing and is sometimes referred to as a hearing de novo (Kaiser Aluminium & Chemical Corporation v Reynolds Metal Co [1969] HCA 7; (1969) 120 CLR 136 at 142 per Kitto J; Commissioner of Patents v Sherman [2008] FCAFC 182; (2008) 172 FCR 394 at [18]–[22]; New England Biolabs Inc v F Hoffmann-La Roche AG [2004] FCAFC 213; (2004) 141 FCR 1 (New England Biolabs) at [44]). As the Full Court of this Court said in New England Biolabs (at [44]):

… The Court approaches the matter for the first time exercising the judicial power of the Commonwealth, not in order to decide whether the executive decision maker was right or wrong, or otherwise to correct error in the executive decision, but to deal with a subject matter, a controversy, for the first time …

Background

3    The background to the opposition to the amendments is as follows.

4    Patent Application No 2009304000 (the Opposed Application) was filed on 15 September 2009 under the provisions of the Patent Cooperation Treaty. At the time of filing, the applicant was Mastitis Research Centre Limited, which was subsequently amalgamated with Bomac Industries Limited, Bomac Laboratories Limited and Bomac Research Limited to become Bayer New Zealand Limited. The applicant’s change of name was recorded on 11 May 2015. The Opposed Application claimed priority from NZ571347, which was filed on 17 September 2008.

5    Merial, Inc opposed the Opposed Application and its opposition was successful on the grounds of a lack of novelty and a lack of an inventive step (Merial, Inc v Bayer New Zealand Limited [2017] APO 27). It will be necessary in due course to say something about the delegate’s findings because of an argument raised on the appeal that the findings are binding on the parties or, in the alternative, give rise to an issue estoppel.

6    Following the delegate’s decision, Bayer New Zealand Limited put forward amendments to the Opposed Application on 27 July 2017 and leave to amend was advertised on 28 September 2017. Merial, Inc filed a notice of opposition to the allowance of the amendments on 27 November 2017.

7    The proposed amendments to the Opposed Application were amendments to Claims 1, 12 and 13. The proposed amendments to Claims 12 and 13 are minor and were, and are, not the subject of any debate. The proposed amendments to Claim 1 give rise to the dispute and are as follows (amendments in bold):

A single formulation, when used for administration to the teat canal or/and lower portion of the teat cistern of a mammary gland of an animal for the prevention of mastitis, wherein the formulation is in the form of a paste, the formulation including:

an oil-based physical barrier material which is able to form a cohesive mass in the teat canal and/or the lower portion of the teat cistern, and

at least one antiseptic compound mixed with the barrier material in sufficient quantity for the antiseptic to act effectively as an antiseptic to kill or prevent the spread of mastitis causing infectious organisms in the teat cistern of the animal following administration;

and wherein the antiseptic is not an acridine.

As will become clear, the significant aspect of the amendments is the exclusion of acridines from the class of antiseptics referred to in Claim 1.

8    The delegate decided that the amendments were allowable under s 102 of the Act and the appeal is from that decision.

The Relevant Legislative Provisions

9    The relevant version of the Act is that which was in force before the amendments made by the Intellectual Property Laws Amendment (Raising the Bar) Act 2012 (Cth) which took effect from 15 April 2013. This was the “old” form of s 102 and s 40(3).

10    Section 102 was in the following terms, relevantly:

102 What amendments are not allowable?

Amendment of complete specification not allowable if amended specification would claim matter not in substance disclosed in the filed specification

(1)    An amendment of a complete specification is not allowable if, as a result of the amendment, the specification would claim matter not in substance disclosed in the specification as filed.

Certain amendments of complete specification are not allowable after relevant time

(2)    An amendment of a complete specification is not allowable after the relevant time if, as a result of the amendment:

(a)    a claim of the specification would not in substance fall within the scope of the claims of the specification before amendment; or

(b)    the specification would not comply with subsection 40(2) or (3).

11    Section 40(3) was in the following terms:

(3)    The claim or claims must be clear and succinct and fairly based on the matter described in the specification.

The relevant part of s 40(3) for present purposes is that part which requires a claim or claims to be fairly based on the matter described in the specification.

The Opposed Application

12    The title of the Opposed Application is “Anti-infective formulation and methods of use” and under the heading “Technical Field”, the reader is told that, more specifically, the invention relates to an anti-infective formulation and methods of use to prevent or ameliorate mammary gland infections, including mastitis.

13    The Opposed Application contains a detailed description of the background art relevant to the invention. A summary of this section is as follows. One of the major problems associated with dairy cows is identified as the high occurrence of bovine mastitis, especially new infections during the dry or drying off period when dairy cows are particularly susceptible to mastitis. The dominant pathogens associated with dry period mastitis infections are identified. The treatments developed in the past to overcome the occurrence of mastitis are described and they include dry cow therapy, external teat seals and internal teat seals. The “significant” disadvantages with the products currently available are identified.

14    Dry cow therapy is the treatment of all cows (healthy and mastitis positive) with antibiotic therapy, which is then described in some detail. The various disadvantages associated with the use of antibiotics are discussed, including the risk of antibiotic residues being absorbed by the animal and excreted in the milk, and:

As a result of this, the milk needs to be withheld for a period of time following antibiotic administration. The use of antibiotics in this manner can also lead to increased risk of the mastitis causing micro-organisms developing resistance to the antibiotic.

15    The disadvantages of withholding milk are identified.

16    Teat seals which involve a physical barrier to prevent microorganisms from gaining access to the teat or udder and the disadvantages of using external teat seals are described.

17    Internal teat seals are described as formulations involving a thick paste that is infused into each quarter of the cow’s udder at drying off. The internal teat seal then forms a physical barrier, either in a paste form or via solidifying in the teat canal, thereby preventing microorganisms from accessing the teat canal. An existing internal teat seal described as “TeatsealTM is identified.

18    The section on Background Art contains the following statement:

It should therefore be appreciated that a product which prevented new infection by pathogenic micro-organisms during the dry period and also avoids altering natural teat sealing processes would be advantageous.

19    Further, it is said by the authors of the Opposed Application that an object of the invention is to address the foregoing problems or, at least, to provide the public with a useful choice.

20    The Opposed Application then contains a section in which it discloses the invention. The first aspect clearly relates to Claim 1. It provides as follows:

According to the first aspect of the present invention there is provided a formulation, for administration to the teat canal or/and lower portion of teat cistern of a mammary gland of an animal, wherein the formulation prior to delivery is in the form of a paste, the formulation including:

an oil-based physical barrier material which is able to form a cohesive mass in the teat canal and/or the lower portion of the teat cistern, and

at least one antiseptic compound mixed with the barrier material.

21    The disclosure of the invention contains a definition of the term “antiseptic” which is as follows:

The term ‘antiseptic’ or grammatical variations thereof refers to any agent that kills or prevents the spreading of infectious organisms in order to prevent the spread of infections. Antiseptics are generally applied to the external surface tissue. Whereas the term ‘antibiotic’ refers to a drug that treats infections internally within the body.

22    There is then a discussion of the viscosity of the paste on pages 8 and 9 of the Opposed Application and the relevance of that for present purposes is that an antiseptic known as chlorhexidine is for the first time referred to in the course of this discussion. On page 11, there is the first of a number of references to one of the desired features of the antiseptic, being the poor absorption of the antiseptic into the cow’s body:

Preferably, the antiseptic may be substantially incapable of being absorbed into the body/cells or metabolised in the teat sinus (or udder). An advantage with this feature is that the antiseptic is readily removed so as not to contaminate the milk supply. This is highly desirable, as the antiseptic remains in the localised area and is virtually incapable of entering the cow’s body physiology.

This is in direct contrast with antibiotics which enters the cow physiology and causes the farmer to withhold milk for a number of milkings, this costing the farmer significantly. Further, a continued application of antibiotics can build up resistance in the microorganisms causing mastitis and it is desirable to be able to avoid using antibiotics as much as possible. …

23    Pages 12 and 13 of the Opposed Application are important because they set out the preferred properties of the antiseptic to be used in the invention and identify by name, or by class, preferred antiseptics. It is convenient to set them out in full:

Ideally, the antiseptic is physiologically acceptable, and have a broad spectrum activity. More preferably, the antiseptic may be at least active against the major and minor pathogens associated with bovine mastitis. This allows the antiseptic to be active against a wide range of micro-organisms, and overcome some of the associated problems with the use of antibiotics – that these are targeted to, and active against an individual, or small related group of micro-organism.

I have marked three passages. These passages are important in terms of the issues and arguments of the parties on the appeal. For identification purposes, I will refer to the first passage as the list of preferable properties for the antiseptic. I will refer to the second passage as references to chlorhexidine. I will refer to the third passage as a reference to four other antiseptics, although I do not overlook that there is more in the passage than that.

24    The Opposed Application contains six examples describing the invention.

25    Counsel for the respondent told me in closing submissions, and I accept, that there are 37 references in the Opposed Application to the antiseptic, chlorhexidine, 16 before the examples and 21 thereafter. Chlorhexidine is the antiseptic used in the examples.

26    I have already set out Claim 1, including the proposed amendments. The balance of the claims with the minor amendments marked are as follows:

2.    A formulation as claimed in claim 1 wherein the physical barrier material includes barium.

3.    A formulation as claimed in claim 2 wherein the barium is in the form of a barium salt.

4.    A formulation as claimed in claim 3 wherein the barium is in the form of barium sulphate.

5.    A formulation as claimed in either claim 3 or claim 4 wherein the barium is micronised.

6.    A formulation as claimed in any one of claims 1 to 5 wherein the antiseptic is in the form of chlorhexidine or salt thereof.

7.    A formulation as claimed in any one of claims 1 to 6 which includes a carrier.

8.    A formulation as claimed in claim 7 wherein the carrier is in the form of oil.

9.    A formulation as claimed in claim 8 wherein oil is paraffin oil.

10.    A formulation as claimed in claim 7 wherein the carrier is a gelling compound.

11.    A formulation as claimed in claim 10 wherein the gelling compound is aluminium stearate.

12.    The use of the formulation as claimed in any one of claims 1 to 11 in the manufacture of a medicament to prevent or ameliorate mastitis.

13.    A method of treating or preventing infection within the teat cistern of a mammary gland characterised by the step of administering a formulation as claimed in any one of claims 1 to 11 into the teat canal or/and lower portion of the teat cistern of the mammary gland of a non-human animal.

14.    The formulation substantially as herein described with reference to Tables 1 – 3 of the “Best Modes” section.

15.    The use of a formulation substantially as herein described with reference to and as illustrated by Examples 3 – 6 of the “Best Modes” section.

16.    A method substantially as herein described with reference to and as illustrated by Examples 1 and 2 of the “Best Modes section.

The Witnesses

27    The witnesses on the appeal were all experts. Each of them swore an affidavit or affidavits and then gave oral evidence in a joint session. In addition, there was a joint expert report prepared by the experts in which they addressed a number of questions.

28    The Court must construe the Opposed Application and expert evidence may assist in the performance of that task. The Opposed Application is not to be construed in the abstract and the Court is “to place [itself] in the position of some person acquainted with the surrounding circumstances as to the state of the art and manufacture” as at the priority date (Kimberly-Clark Australia Pty Ltd v Arico Trading International Pty Ltd [2001] HCA 8; (2001) 207 CLR 1 (Kimberly-Clark) at [24]). Some of the expert evidence in this case tended to be expressed in terms of how the invention would be put into effect. The question is, however, how the disclosure in the Opposed Application would be understood by persons skilled in the relevant art.

The Appellant’s Expert Witnesses

29    The appellant relied on the evidence of three experts, Professor Mark Wainwright, Professor Edward Whittem and Professor Richard Laven.

30    Professor Wainwright affirmed two affidavits, the first on 9 October 2019 and the second on 31 May 2020. He is Professor of Antimicrobial Chemotherapy in the School of Pharmacy and Biomolecular Sciences at Liverpool John Moores University.

31    Professor Wainwright has a Bachelor of Sciences (with Honours) in chemistry from Leicester University and a Doctor of Philosophy in photoconductive polymers from the University of Leeds. He has over 30 years of experience in antimicrobial chemotherapy both in academia and in industry. His research has focused on medicinal chemistry and, in particular, antimicrobial synthesis and testing, specifically the identification, synthesis and study of antimicrobial compounds which have activity against microbial organisms including bacteria, fungi, viruses and protozoa. Professor Wainwright has authored over 120 papers in refereed journals in the field of antimicrobial chemotherapy, as well as a monograph and he has contributed many chapters to books in that field. He has acted as referee for a number of refereed journals in the field and has been an invited speaker and has presented at over 45 different international conferences.

32    Professor Whittem affirmed two affidavits, the first on 11 October 2019 and the second on 1 June 2020. He is Professor and Chair of Veterinary Clinical Sciences at the University of Melbourne and the director of Djanowot Pty Ltd, which is his own consultancy business providing services to Australian and New Zealand animal health industries.

33    Professor Whittem has a Bachelor of Veterinary Science from the University of Melbourne and a Doctor of Philosophy in Veterinary Pharmacology from the University of Georgia. He has over 25 years of experience in the field of veterinary pharmacology and toxicology, including as the Head of Research and Development at a veterinary pharmaceutical manufacturing company, in which capacity he oversaw the development of an intramammary antibiotic formulation to treat bovine mastitis. He has authored and co-authored a number of peer-reviewed journal articles, some of which relate to treatment options for bovine mastitis. He has undertaken regular manuscript reviews for several peer-review journals in the field and has regularly attended and spoken at veterinary conferences and other professional forums relating to veterinary pharmacology and toxicology.

34    Professor Laven swore an affidavit on 4 June 2020. He is Professor in Production Animal Health at the Institute of Veterinary, Animal and Biomedical Sciences at Massey University.

35    Professor Laven has a Bachelor of Veterinary Medicine (with Distinction) in Veterinary Public Health, and a Doctor of Philosophy in veterinary science from the University of London. His current role involves conducting research into the major health and welfare issues of cattle, particularly lameness, mastitis and fertility. During his time at Massey University, Professor Laven has had clinical responsibilities as part of its commercial farm animal practice. He was previously employed as Manager of the Veterinary Laboratory at the Scottish Agricultural College disease surveillance laboratory, with mastitis diagnosis and control being a major part of the laboratory’s workload. Professor Laven has published over 150 peer-reviewed articles, over 25 of which related to mastitis, and is an author and editor of a leading textbook in the field: Parkinson TJ, Vermunt JJ, Malmo J and Laven R, Diseases of Cattle in Australasia (2nd ed, Massey University Press, 2019). He is currently a member of the Editorial Boards of a number of leading journals in veterinary medicine and animal health and has presented over 100 presentations at conferences, of which more than 15 have involved mastitis.

The Respondent’s Expert Witnesses

36    The respondent relied on the evidence of three experts, Professor Gregory Cook, Professor Jonathan Huxley and Associate Professor Craig Bunt.

37    Professor Cook affirmed an affidavit on 13 February 2020. He is Professor of Microbiology and Head of Department of the Department of Microbiology and Immunology at the University of Otago.

38    Professor Cook has a Bachelor of Sciences, a Master of Sciences (with Honours) and a Doctor of Philosophy in Microbiology from the University of Waikato. He has over 27 years of experience working as a microbiologist, specifically in microbial physiology and biochemistry, antimicrobial resistance, drug discovery, molecular biology and structural biology. His work as a microbiologist has included projects relating to treating agents for bovine mastitis. From 1992 to 1995, he worked as a rumen (dairy cow) microbiologist at Cornell University. He has over 200 publications in the field and has been invited to write regular reviews and book chapters on the subject of cellular and molecular bacterial physiology and energetics.

39    Professor Huxley affirmed an affidavit on 14 February 2020. He is Professor of Dairy Cow Health and Head of the School of Veterinary Science at Massey University.

40    Professor Huxley has a Bachelor of Veterinary Medicine from the Royal Veterinary College and a Doctor of Philosophy in bovine mastitis from the University of Bristol. His PhD dissertation was entitled: “An Assessment of Non-Antibiotic Approaches to Mastitis Control in the Dry Period and Their Impact on Intramammary Infection Dynamics”. As part of his PhD research, Professor Huxley conducted a study that compared the efficacy of a non-antibiotic internal teat sealer containing bismuth subnitrate to antibiotic dry cow therapy. He has over 24 years of experience as a veterinarian and in academia in the United Kingdom and more recently in New Zealand, and has had more than 70 peer-reviewed papers published, including on topics relating to the causes, treatment and prevention of bovine mastitis. Professor Huxley is also the author of various book chapters, editorials and more than 100 clinical and conference papers and letters.

41    Associate Professor Bunt affirmed an affidavit on 14 February 2020. He is Associate Professor in Animal Science in the Faculty of Agriculture and Life Sciences at Lincoln University.

42    Associate Professor Bunt has a Bachelor of Pharmacy (with Honours) and a Doctor of Philosophy in pharmaceutical sciences from the University of Otago. He has over 24 years of experience working as a pharmaceutical formulation scientist. His work has focused on new ways to formulate difficult-to-deliver molecules for veterinary pharmaceutical, agricultural and nutraceutical applications and he has an active research program in this area as well as experience as a Research Officer with a veterinary controlled release pharmaceutical company, focusing on developing new pharmaceutical technologies for intravaginal, intrarumenal, intramammary and parenteral routes of drug delivery. Associate Professor Bunt is the author of over 150 research publications, is a named inventor on 16 granted patents and patent applications and has attended and presented at numerous professional conferences and workshops, both nationally and internationally.

43    As a general comment at this stage, it may be said that each expert was qualified and doing his best to assist the Court within his particular field of expertise.

Bovine Mastitis and Key Terms and Concepts

44    It is convenient to briefly describe bovine mastitis and to identify some key terms and concepts.

45    In his first affidavit, Professor Whittem was asked to describe bovine mastitis, including its common causes, prevention and treatment. The description of those matters given by Professor Whittem is not disputed, save for one matter with respect to which Professor Huxley disagreed and it will be sufficient at this point to note that area of disagreement.

46    Mastitis is the inflammation of an animal’s mammary gland or udder and bovine mastitis refers to the incidence of this disease in cows. The terms “udder” and “mammary gland” are often used interchangeably, although the udder is the single organ located on the underside of female cows which consists of four separate mammary glands. When a cow is lactating, i.e. milking, milk is produced in the mammary glands and evacuated through the streak canal, which is the entrance of the mammary gland located on the teat.

47    Adult lactating cows are most at risk of infection and mastitis and a lactating cow may contract mastitis at any time during its lactation cycle. The lactation cycle is the period between one calving and the next and comprises the “lactation period”, when the cow is producing milk, and the “dry period”, which is the time between lactations when the cow is rested.

48    Mastitis usually results from an infection of the udder which can be caused by pathogens, including bacteria and a bacterial infection is the most common cause of mastitis in cows. Bacterial species can be broadly divided into Gram-positive bacteria and Gram-negative bacteria, both of which cause bovine mastitis. A cow’s response to a bacterial infection will often be determined by the area of the mammary gland the bacteria access and infect, i.e.:

(1)    Bacteria which are present only in the teat generally do not cause an inflammatory response.

(2)    Bacteria which infect the areas of the mammary gland which store the cow’s milk are relatively non-invasive and will usually prompt only mild inflammation. The inflammatory response operates to attract immune system cells to the infected area which kill and remove the infecting bacteria.

(3)    Bacteria which are able to cross the barriers between the milk and the tissue to infect the interstitial tissue of the mammary gland usually cause significant tissue injury and will prompt a more serious inflammatory response. Once the bacteria are killed this inflammation usually heals reasonably well.

(4)    Some bacteria which infect tissues may also gain access to the inside of the inflammatory or immune system cells and hide from the immune system response. This kind of infection can result in permanent damage to the form and function of the infected tissue and can cause the cow to cease producing milk. One such invasive species of bacteria that is able to access the inside of inflammatory cells is the Gram-positive bacteria, staphylococcus aureus.

49    Mastitis can be described as clinical or sub-clinical. Clinical mastitis is visible through changes in milk quality, the shape and function of the udder or to the general health and wellbeing of the cow. Sub-clinical mastitis is mild and does not cause noticeable clinical indications, but can be identified through laboratory testing.

50    Mastitis can be acquired directly by contact with bacteria that are free in the cow’s environment, referred to as “environmental pathogens”, or by exposure of the udder to bacteria spread through, for example, human contact or milking machinery, referred to as “contagious pathogens”. Professor Whittem says that mastitis in dry cows is generally caused by bacteria which are present in the udder at the start of the dry period having initially entered during the lactation period, whereas Professor Huxley emphasises that this is only true of sub-clinical mastitis and such infections rarely cause clinical mastitis during the dry period. Clinical mastitis and new intramammary infections acquired during the dry period are almost exclusively caused by environmental pathogens given the limited exposure to contagious pathogens during the dry period.

51    The entry of pathogens into the udder and likelihood of the cow contracting mastitis is restricted through the udder’s natural teat sealing process, whereby the streak canal closes over through the contraction of a surrounding muscle in the form of a sphincter. At the start of the dry period, the streak canal closes more tightly and the udder secretes keratin, forming a plug, before the plug is naturally removed through the evacuation of milk when the cow begins to milk at the start of the lactation period.

52    There are a range of preventative measures which aim to prevent bacteria from entering the udder or at least reduce the number of bacteria that are able to enter the udder to a non-infectious amount or dose. Preventative measures are directed at reducing the sources of infection for lactating cows given that the udder is unsealed during the lactation period, which contributes to the risk of bacterial infection. Antiseptics are commonly applied as a preventative measure to ensure the udder is clean and disinfected, reducing the potential sources of infection for lactating cows. Another preventative measure, applied at the start of the dry period, is an intramammary antibiotic formulation infused into the udder, forming a deposit and gradually releasing the antibiotic which acts on any bacteria entering the udder. A teat seal product may also be used as a preventative measure, which mimics and augments the natural teat sealing process. Teat seals may be either internal or external and internal teat seals are infused into the mammary gland, forming a plug, while external teat seals usually comprise a polymerising gel into which the teat is dipped.

53    An existing infection causing clinical or pre-clinical mastitis in a cow may be treated through a number of therapeutic strategies. Treatment of clinical mastitis is frequently directed at lactating cows because it tends to be diagnosed through changes in the milk or to the udder which are more detectable during milking. One therapeutic strategy is a fast-acting antibiotic intramammary infusion, similar to that which is administered at the start of the dry period and described above (at [52]), but designed to release the antimicrobial compound as quickly as possible after administration so as to disperse and inhibit bacteria in the udder. Another treatment option which is less common in Australia is an antibacterial intramuscular injection. Intrammamary infusions are preferred partly because of their more predictable milk withholding period, which is the period in which drug residues are present in the tissue or milk before falling to a level considered non-threatening to human health or food manufacture.

54    Treatment strategies may be paired with one or more preventative measures to ensure that while the cow is being treated, it does not contract any new infections.

55    The following identification of some key terms and concepts is based on the evidence of Professor Wainwright. The extent to which these matters were common general knowledge before 17 September 2008 is a separate issue which is dealt with later in these reasons.

56    Chemotherapy encompasses all uses of chemicals for therapy. As a field of study, chemotherapy encompasses the treatment of all types of infections or conditions using chemicals, although today it is most commonly associated with the chemical treatment of different types of cancers. The first applications of chemotherapy were antimicrobial, being the treatment of protozoal disease with chemicals.

57    An antimicrobial compound works against or destroys microbes. Microbes include bacteria, fungi, viruses and protozoa. The term “antimicrobial” is an umbrella term. Antimicrobial compounds include antibiotics, antiseptics, antibacterials, disinfectants, antifungals, antivirals and antiprotizoals.

58    The word “antibiotic” traditionally referred to a compound that was created by a microorganism through natural synthesis, or derived from nature, and used to treat infection usually by bacteria. An example of an antibiotic is benzylpenicillin, which was traditionally derived from the penicillium mould and is used to treat a range of infections caused by bacteria. By September 2008, the term “antibiotic” was most commonly used to refer to compounds or drugs being used to treat bacterial infections specifically (and not, for example, viral or protozoal infections), regardless of how the compounds or drugs were made. The meaning of “antibiotic” has evolved over time and before September 2008, the term was used by some to refer to tumour “antibiotics” that are derived from natural moulds or bacteria, such as anthracyclines. These tumour antibiotics interfere with the DNA inside cancer cells to prevent replication. Whilst antibiotics are often administered systematically through oral or intravenous administration, some antibiotics are applied locally. For example, tetracycline cream is applied externally to prevent the growth of acne-causing bacteria.

59    An antiseptic is, generally speaking, a compound that is applied locally to humans or animals, rather than systematically, to kill or prevent the growth of microbes, including bacteria. Antiseptic compounds are commonly applied to the external surface of humans and animals. A number of antiseptics are also applied locally in internal cavities of humans and animals. For example, chlorhexidine is an antiseptic that is commonly included in mouthwash, in order to kill or prevent the growth of bacteria. An antiseptic should kill or prevent the growth of the target microbe without causing toxicity to, or damaging, the human or animal. Because antiseptics are generally administered locally, an antiseptic should not be toxic to the human or animal at the site of administration. The antimicrobial activity of a compound is measured in units called “Minimum Inhibitory Concentration”. This is the lowest concentration of an antimicrobial compound required to inhibit the growth of a given microorganism. The toxic concentration of a compound is the concentration at which that compound will cause significant harm to a human or animal. In order for an antiseptic compound to be safe and effective for use in products administered to humans and/or animals, its relevant minimum inhibitory concentration must be lower than its toxic concentration and the administered dose must deliver a concentration that is lower than its toxic concentration. An antiseptic compound must be able to kill or prevent the growth of microbes at the pH of the environment where it is applied. The antiseptic activity of a compound is influenced by the pH of the environment, because the pH of an environment can influence the charge and ionisation state of that compound.

60    Both Gram-positive and Gram-negative bacteria have a plasma membrane. However, unlike Gram-positive bacteria, Gram-negative bacteria have an additional outer membrane.

61    Examples of antiseptics which were part of common general knowledge before 17 September 2008 include benzalkonium chloride (BZK), cetrimide, chlorhexidine, iodophors and triclosan. The question of whether antiseptic acridines were part of common general knowledge before 17 September 2008 is addressed later in these reasons.

62    A quaternary ammonium compound (QAC) is a permanently positively charged organic nitrogen compound, in which the nitrogen atom makes four covalent bonds to carbon atoms. Many, but not all, QACs are antiseptics. Cetrimide, BZK, euflavine and sinflavin are examples of QACs that are antiseptics. Acriflavine is a QAC because the major component of acriflavine is euflavine chloride and euflavine chloride is a QAC. The proflavine hydrochloride, which is a minor component of acriflavine, is a by-product of the euflavine chloride manufacturing process. The issue of whether it was common general knowledge before 17 September 2008 that acriflavine is a QAC is addressed later in these reasons. QACs include antiseptic acridines in which the ring nitrogen atom is alkylated and permanently positively charged, such as sinflavin and euflavine.

63    The general term “ionisation” refers to the loss or the gain of an electron from an atom or molecule. One electron has a formal negative charge of -1. Where a neutral molecule or atom “loses” or “donates” an electron, it is converted into a positively charged ion (a “cation”), and it adopts a formal positive charge. Where a neutral molecule or atom “gains” or “accepts” an electron, it is converted into a negatively charged ion (an “anion”), and it adopts a formal negative charge. Cetrimide, BZK and chlorhexidine are all ionised antiseptics at physiological pH. Cetrimide and BZK are permanently positively charged QACs. Chlorhexidine is a protonated nitrogen cation at physiological pH. They are characterised by cationic ionisation and are positively charged (cationic) species. Antiseptic acridines that are substituted at the ring nitrogen with an alkyl group, such as euflavine and sinflavin, are permanently positively charged QACs. Antiseptic acridines in which the ring nitrogen makes a covalent bond to a hydrogen atom at physiological pH, such as proflavine and 9-aminoacridine, are protonated nitrogen cations at physiological pH.

64    Acridines have a particular general chemical structure described by Professor Wainwright. The term “acridines” includes acridine derivatives. Not all acridine derivatives are antiseptics and the antiseptic activity of acridine derivatives is dictated by the position and nature of the substituted group on the acridine core. Not all antiseptic acridines are QACs. Permanently positively charged acridine derivatives, such as euflavine and sinflavin, are QACs. The meaning of intercalating DNA in the case of antiseptic acridines is that the antiseptic slips between the layers of nucleic acid base pairs of bacterial DNA and disrupts the DNA double helix. The intercalation prevents cell replication and protein transcription and so prevents the growth or reproduction of bacterial cells. Examples of antiseptic acridines are euflavine, proflavine, sinflavin and 9-aminoacridine also known as aminacrine. Acriflavine is also an acridine. As previously stated, it is a mixture of euflavine chloride and a minor amount of proflavine hydrochloride.

The Decisions of the Delegate

65    There are two relevant decisions of the delegate: the decision on the substantive opposition proceeding and the decision on the amendment application. As I have made clear, this is a rehearing and it is no part of this Court’s task on the appeal to determine whether the delegate erred. Nevertheless, the delegate’s decisions provide helpful background and, more importantly, are relevant in view of the argument that certain findings he made are binding on the parties.

The Delegate’s Decision on the Substantive Opposition Proceeding

66    The delegate held that each of Claims 1 and 7–13 lacked novelty in light of cited prior art and that each of Claims 1–4 and 713 lacked an inventive step in light of cited prior art and the common general knowledge. The prior art which led to the finding of a lack of novelty was GB2,273,441 and NZ258199. NZ258199 is the New Zealand equivalent of GB2,273,441. The delegate found that GB2,273,441 was published on 22 June 1994 and NZ258199 was published on 29 January 1997 and that both were part of the prior art base. The delegate held that Claim 1 in the Opposed Application lacked novelty in light of each citation considered separately.

67    The delegate reached the following conclusion in the course of his consideration of novelty (at [126]):

I conclude that 0.1% (w/w) acriflavine in the teat seal formulations of D1 [GB2,273,441] and D1A [NZ258199] is an amount of antiseptic that falls within the scope of “sufficient quantity to act effectively as an antiseptic” of claim 1 as assessed by an in vitro assay or in an in vivo environment of the animal.

68    It is significant in terms of the arguments put on this appeal that, as part of his consideration of inventive step, the delegate found that it was part of the common general knowledge that acriflavine had an antiseptic property (at [198]). He also found that it would be part of the background knowledge of a person skilled in the art that acriflavine is an antiseptic and a dye (at [207]).

69    The delegate found that the invention in Claim 1 was obvious in light of GB2,273,441 considered together with common general knowledge. The delegate said (at [230]):

Whilst D1 [GB2,273,441] does not disclose acriflavine to be an antiseptic, this is of no consequence because I have previously found the teat seal formulation of D1 contains acriflavine in sufficient quantity to act effectively as an antiseptic. The question for the purposes of inventive step is what would a skilled person have done as a matter of routine in light of the teaching of D1? I have previously found it was part of the CGK to use an artificial teat seal formulation to provide a physical barrier to seal off the teat canal. Therefore, I conclude that it would have been a matter of routine for a skilled person to follow the teaching of D1 and administer the teat seal formulation of D1 to seal the teat canal or lower portion of the teat cistern of an animal for the prevention of mastitis. Therefore, I conclude claim 1 lacks inventive step in light of D1 considered together with CGK.

70    It is convenient to note at this point a submission made by the respondent. The respondent submitted that if it is bound by the delegate’s finding that it was common general knowledge that acriflavine had an antiseptic property, then other findings are also relevant. Those findings were as follows: (1) the delegate found that the evidence did not establish that teat seal formulations containing acriflavine was part of the common general knowledge (at [201]); and (2) the delegate found that the evidence did not establish that it was part of the common general knowledge that acriflavine was used in teat seal formulations to provide an antiseptic effect in the animal (at [204], [207] and [208]). The respondent submitted that an absence of findings by the delegate as to the following matters is also relevant: (1) there was no finding by the delegate that acridines were common general knowledge and the existence of acridines was not found to be common general knowledge; (2) there was no finding that it was common general knowledge that any acridines might be characterised as QACs; (3) there was no finding by the delegate that it was common general knowledge that any acridines might be ionised antiseptics; (4) there was no finding by the delegate that it was common general knowledge that any acridine had any of the preferred properties or characteristics identified in the Opposed Application; and (5) there was no finding by the delegate that it was common general knowledge that acriflavine is an acridine, or that acriflavine is a QAC or an ionised antiseptic, or that acriflavine has any of the preferred characteristics identified in the Opposed Application.

The Delegate’s Decision on the Amendment Application

71    The key findings and conclusions of the delegate were as follows:

(1)    The ground of opposition to the amendments before the delegate was that as a result of the amendments, the specification would not comply with s 40(3) and, therefore, was not allowable by reason of s 102(2)(b);

(2)    The delegate reiterated his earlier finding that it was part of the common general knowledge that acriflavine has an antiseptic property;

(3)    A QAC has a permanent positive charge on the nitrogen;

(4)    Acriflavine is an acridine which is a QAC as is any other acridine which has a permanent positive charge on the ring nitrogen;

(5)    QACs are a class of compounds which includes acridines and non-acridines;

(6)    Fair basis is determined by asking whether there is a real and reasonably clear disclosure in the body of the specification of the subject matter that is claimed;

(7)    It follows from the finding that it is part of the common general knowledge that acriflavine has an antiseptic property that the person skilled in the art would understand acriflavine to be one of a number of options of antiseptics taught by the specification of the Opposed Application;

(8)    Chlorhexidine is not an acridine. Cetrimide and BZK are QACs which are not acridines;

(9)    There is no need to determine the contention by the applicant for the amendments that acridines have properties contrary to those listed on page 12 of the Opposed Application; and

(10)    Acridines are not mentioned or exemplified in the specification of the Opposed Application and the amendments are not fundamentally inconsistent with the specification of the Opposed Application.

72    It is worth making the brief reference to the appellant’s Notice of appeal, not because of the need to identify error in the delegate’s decision, but because it provides some indication of the main arguments put on the appeal. The Notice of appeal contains a contention that the delegate erred in finding that the amendment to the Opposed Application was allowable within the meaning of s 102 of the Act and identifies the specific errors as follows:

(1)    The delegate erred in identifying the relevant question as being whether the specification of the Opposed Application provides a real and reasonably clear disclosure of formulations in which the antiseptic is not an acridine, rather than whether the specification of the Opposed Application provides a real and reasonably clear disclosure of an invention in which acridine is excluded from use as an antiseptic in the claimed formulations;

(2)    The delegate erred in deciding that Claim 1, as a result of the amendment, was not fundamentally inconsistent with the specification of the Opposed Application;

(3)    The delegate erred in deciding that the specification of the Opposed Application as filed and the specification of the Opposed Application as amended contained a real and reasonably clear disclosure of what is claimed as a result of the amendment;

(4)    The delegate erred in deciding that a lack of fair basis under s 40(3) of the Act had not arisen as a result of the amendment; and

(5)    The delegate erred in deciding that the specification of the Opposed Application as amended complied with s 102(2)(b) of the Act and that the amended claims were fairly based on matter described in the specification.

73    The appellant asserted in the Notice of appeal that the delegate ought to have found that the opposition was made out, in that, as a result of the amendment, the specification of the Opposed Application would not comply with s 40(3) of the Act, such that the amendment was not allowable under s 102(2)(b) of the Act.

74    The appellant asserted in the Notice of appeal that this Court should refuse the amendment because of the following: (1) as a result of the amendment, the specification of the Opposed Application would not comply with s 40(3) of the Act, such that the amendment is not allowable under s 102(2)(b) of the Act; (2) further or alternatively, as a result of the amendment, the specification would claim matter not in substance disclosed in the specification as filed, such that the amendment is not allowable under s 102(1) of the Act; or (3) further or alternatively, the amendment should be refused in the exercise of the Court’s discretion.

75    The respondent filed a Notice of contention it which it contended that the decision of the delegate should be affirmed on grounds other than those relied on by him and, in particular, on the ground that the specification as filed contained a real and reasonably clear disclosure of the invention as defined in Claim 1, including the limitation “wherein the antiseptic is not an acridine”, given that the specification described various optional properties of an antiseptic as being preferable for the working of the claimed invention, including at pages 12 and 13, and acridines lack all or most of those preferable properties.

The Relevant Legal Principles on an Amendment Application

76    The following legal principles are not contentious.

77    First, the requirement of substantial disclosure in s 102(1) is very similar to the requirement that a claim must be “fairly based” on matter disclosed in the specification (s 102(2)(b) and s 40(3)) (Gambro Pty Ltd v Fresenius Medical Care South East Asia Pty Ltd [2000] FCA 1044; (2000) 49 IPR 321 at [18]; ICI Chemicals & Polymers Ltd v Lubrizol Corporation Inc [2000] FCA 1349; (2000) 106 FCR 214 at [118]). The appellant accepted that the test was, as it put it, “very similar”.

78    Secondly, the general approach to s 102 is to give the section a broad and liberal construction. In United States Gypsum Company v CSR Building Products Ltd [2017] FCA 595 (United States Gypsum), Moshinsky J said (at [38]):

It is “a well settled approach that the requirements of s 102 should generally be given a liberal construction”: Gambro Pty Ltd v Fresenius Medical Care South East Asia Pty Ltd (1999) 48 IPR 625 at [25] per Tamberlin J. The phrase “not in substance disclosed” should be interpreted in “a broad common sense way”: Ethyl Corporation’s Patent [1972] RPC 169, applied in Gambro at [25]. It has also been said that a liberal approach should be adopted “so as to permit any fair amendment which had previously been disclosed”: Gambro at [25], citing Ethyl Corporation’s Patent.

79    Thirdly, s 102(1) requires the Court to first identify what is the amendment and that is done by comparing the specification as filed and the specification read as if amended in the manner sought. The next question is whether, by reason of the amendment sought, the specification would claim matter not in substance disclosed in the specification as filed. Justices Carr and Goldberg said the following in RGC Mineral Sands Pty Ltd v Wimmera Industrial Minerals Pty Ltd [1998] FCA 1358; (1998) 89 FCR 458 (RGC Mineral Sands) at 466:

… The subsection focuses on the amendment proposed and it must be that amendment which has the result of pushing the claimed matter over the line defined by the expression “matter not in substance disclosed in the specification as filed”. The key point to keep in mind is, as counsel for the respondent contended (in our view correctly), that the words “as a result of the amendment” are not to be confused with the expression “after the amendment”.

(Emphasis in original.)

80    Fourthly, the leading Australian authority on the meaning of the requirement in s 40(3) that the claim or claims be fairly based on the matter described in the specification is Lockwood Security Products Pty Ltd v Doric Products Pty Ltd [2004] HCA 58; (2004) 217 CLR 274 (Lockwood No 1). In that case, the High Court said that the comparison which s 40(3) calls for between a claim and the matter disclosed in the specification is not analogous to the comparison between a claim and an alleged anticipation or infringement (at [68]). The Court also said, citing an authority of this Court (CCOM Pty Ltd v Jiejing Pty Ltd [1994] FCA 1168; (1994) 51 FCR 260 at 281), that it is an error to approach the application of s 40(3) by employing “an over meticulous verbal analysis” and to seek to isolate in the body of the specification “essential integers” or “essential features” of the alleged invention and to ask whether they correspond with the essential integers of the claim in question (at [68]). The test is whether there is “a real and reasonably clear disclosure” (Société des Usines Chimiques Rhône-Poulenc v Commissioner of Patents [1958] HCA 27; (1958) 100 CLR 5 at 11 per Fullagar J) and attention must be directed to the construction of the specification as a whole, “putting aside particular parts which, although in isolation they might appear to point against the ‘real’ disclosure, are in truth only loose or stray remarks” (at [69]).

81    The Court in Lockwood No 1 also identified the following principles. First, the terms of s 40(3) require one to split the claims from the specification or body of the specification to see if the former are fairly based on the matter disclosed in the latter (at [49]). Secondly, the terms of s 40(3) are such that the subsection does not call for an inquiry into an “inventive step” or inventive “merit” or a “technical contribution to the art”. The relevant comparison is between the claims and what is described in the specification only (at [54]). Thirdly, the issue of fair basis involves a narrow question of whether the claim to the product being new, useful, and inventive, that is to say, the claim as expressed, travels beyond the matter disclosed in the specification (Olin Corporation v Super Cartridge Co Pty Ltd [1977] HCA 23; (1977) 180 CLR 236 (Olin) at 240 per Barwick CJ; Kimberly-Clark at [15]; Lockwood No 1 at [57]). Finally, the Court said that in determining whether an invention is fairly based, it is necessary to take into account common general knowledge so far as it casts light on questions of construction and what is said about the invention in the specification independently of whether it is a “patentable invention” and, in particular, independently of whether it is a patentable invention on the ground that it is not obvious (at [72]). The Court in Lockwood No 1, in the course of identifying difficulties with the respondent’s submissions in that case, said (at [83]):

The first [difficulty] is that the statutory test as expounded by Barwick CJ does not call for any evaluation of whether the breadth of the claims exceeds “the technical contribution to the art embodied in the invention”, merely for an evaluation of whether the claims travel beyond the matter described in the specification.

82    The test of “travelling beyond” referred to in Olin and Lockwood No 1 was applied by Lindgren J in Emperor Sports Pty Ltd v Commissioner of Patents [2005] FCA 996; (2005) 146 FCR 159 (Emperor Sports) (at [82]) in the context of the application of s 102(1) in the sense that in that context, his Honour said that the question is whether the matter claimed by the specification as a result of the amendment travel beyond matter in substance disclosed in the specification as filed.

83    In this case, and putting the matter very generally at this point, the effect of the proposed amendments is to reduce a large class of compounds covered by the Opposed Application to a smaller, albeit still very sizeable, class and submissions of the parties were directed to cases addressing the resolution of the not in substance disclosed and fair basis issues in that context or similar contexts.

84    In AMP Incorporated v Hellerman, Ltd [1962] 1 All ER 673; [1962] RPC 55, a majority in the House of Lords allowed an amendment which limited the scope of a claim. The invention in the complete patent specification in that case was a crimping tool for crimping electrical connectors onto electrical conductors so as to form a secure electrical connection. The principal feature of the invention was a pawl and ratchet device which predetermined the final position of the jaws. An optional feature was the addition of a “stop” consisting of opposing prolongations of the jaws which was the subject of a separate claim. The specification contemplated crimping tools made under it either with or without the “stop”. An amendment to the specification sought to make the “stop” an essential feature of the invention.

85    The House of Lords by a majority reversed the decision of the Court of Appeal and allowed the amendment under s 31(1) of the Patents Act, 1949 (UK) which read as follows:

After the acceptance of a complete specification, no amendment thereof shall be effected except by way of disclaimer, correction or explanation, and no amendment thereof shall be allowed, except for the purpose of correcting an obvious mistake, the effect of which would be that the specification as amended would claim or describe matter not in substance disclosed in the specification before the amendment, or that any claim of the specification as amended would not fall wholly within the scope of a claim of the specification before the amendment.

86    Lord Denning (with whom Lord Radcliffe agreed) held that the amendment was a disclaimer within s 31(1) because the patentee disclaimed all crimping tools without stops and limited his claim to crimping tools with stops. The next question was whether a crimping tool with a stop was in substance disclosed in the specification. Lord Denning held that clearly it was and that it was not relevant to consider whether the stop before amendment was distinctive or part of the inventive step. His Lordship said (at 688–689):

It is no longer necessary to inquire into the niceties of inventive steps. It is only necessary to see whether the matter was in substance disclosed in the original specification and that it clearly was. The tool with a stop was disclosed as well as the tool without a stop. The patentee disclaims the tool without a stop and confines himself to the tool with a stop. I see no bar in the Act of 1949 to this amendment.

I would agree that if the amendment had introduced an entirely new integer, that is to say, a feature that had not been disclosed in the specification previously, then it could not have been allowed. But here there is no new integer. The “stop” was clearly disclosed in the original specification. All that is done is to make it an essential feature, whereas it was previously optional. And this, in my opinion, is permissible under the Act of 1949.

(Emphasis in original. See also at 685 per Lord MacDermott and see further Lord Denning MR in Ethyl Corporations Patent [1972] RPC 169 at 194 and RGC Mineral Sands at 468 per Carr and Goldberg JJ.)

87    The decision of the Full Court of this Court in AstraZeneca AB v Apotex Pty Ltd [2014] FCAFC 99; (2014) 226 FCR 324 (AstraZeneca) was the subject of detailed submissions by the parties.

88    The issue in that case of present relevance was the priority date for the 842 or cation patent and that issue turned on whether the amendment to the patent meant that the claims of the complete specification claimed matter that was in substance disclosed as a result of amending the specification (s 114(1) of the Act (as it was at the time relevant to the decision) and reg 3.14 of the Patents Regulations 1991 (Cth)).

89    Prior to the amendment, the specification clearly indicated that phosphate may be used as the counter anion in the compositions of the invention. The amendment made it clear that compositions that use phosphate for that purpose are not within the scope of the claimed invention.

90    The Court noted that s 114(1) and reg 3.14 complemented s 102(1) and noted that the issue arising under s 114(1) and reg 3.14 required the Court to apply a test that is closely related to, if not quite the same as, the test for fair basis under s 40(3) of the Act. The Court referred to Lockwood No 1. AstraZeneca submitted that the effect of the amendment was to narrow the scope of the claims, in that compositions in which phosphate was the counter anion in the composition was no longer claimed.

91    In addressing this submission, the Court said (at [244]):

We do not accept that s 114(1) can never be engaged in circumstances where the claim in question claims less than what was described in the specification immediately prior to the amendment. A very general description of an invention in a specification before amendment might not contain a real and reasonably clear disclosure of more specific embodiments of the invention subsequently disclosed and claimed after amendment. Similarly, in the case of a claim to a pharmaceutical formulation, the description of the invention in the specification before amendment might allow for the use of particular classes of chemicals with which to make the formulation, while the amended claim might positively exclude their use for that purpose. Whether or not there is a real and reasonably clear disclosure in the specification before amendment of what is claimed in such circumstances is the question that arises in this case.

92    The Court gave two examples of circumstances in which in substance disclosure as a result of amending the specification did not occur even though the effect of the amendment is to claim less than what was described in the specification immediately prior to the amendment and they are as follows: (1) a very general description of an invention in a specification before amendment might not contain a real and reasonably clear disclosure of more specific embodiments of the invention subsequently disclosed and claimed after amendment; and (2) in the case of a claim to a pharmaceutical formulation, the description of the invention in the specification before amendment might allow for the use of particular classes of chemicals with which to make the formulation, while the amended claim might positively exclude their use for that purpose.

93    The Court accepted the following: (1) the logical consequence of the amendment was that the amended claims claimed something less, not more, than previously described; and (2) there was nothing in the unamended specification to indicate that the use of phosphate as the counter anion was an essential aspect of the invention described, nor were phosphates one of the “[e]specially preferred counter anions” (at [245]–[246]).

94    The Court held that the amendment fell within the terms of s 114(1) for the following reasons (at [247]):

However, the specification states that dibasic calcium phosphate and tribasic calcium phosphate are preferred inorganic salts, and tribasic calcium phosphate is the inorganic salt used in each of the Examples (Examples 1 to 4) of the pharmaceutical compositions of the invention described in detail in the specification. In each of these compositions the phosphate is the counter anion to the inorganic salt. This is fundamentally inconsistent with the revised form of claims and the additional matter introduced as a result of the 2005 amendments. Not only does the specification before amendment not suggest that phosphate not be used as the counter anion in the inorganic salts used in the pharmaceutical compositions of the invention, it positively recommends that it be used for that purpose. We are satisfied that the unamended specification does not contain a real or reasonably clear disclosure of what was claimed as a result of the 2005 amendments.

95    The appellant put its arguments at two levels. First, before amendment there is simply no disclosure that the antiseptic to be used in the formulation was not to be an antiseptic acridine. Secondly, antiseptic acridines were preferred antiseptics and it is inconsistent to have amended claims which exclude them. Also, the appellant makes the point that the phosphate in AstraZeneca, like the antiseptic acridines in this case, was not the most preferred embodiment. There is, according to the appellant, no general principle that there is a real and reasonably clear disclosure merely because the amendments result in a narrowing of the claim.

96    The Full Court of this Court in addressing an issue of external fair basis in Idenix Pharmaceuticals LLC v Gilead Sciences Pty Ltd [2017] FCAFC 196; (2017) 134 IPR 1 (Idenix), and after referring to the Full Court’s remarks in AstraZeneca at [247], said (at [293]):

Accordingly, there was an inconsistency between the revised claims and the relevant “matter” with which it was being compared for the purposes of fair basis, being the specification prior to amendment. Inconsistency between the matter said to disclose the invention and the invention points against there being a real and reasonably clear disclosure of the invention. In Sigma Pharmaceuticals (Australia) Pty Ltd v Wyeth (2011) 119 IPR 194; [2011] FCAFC 132, claims unlimited to a particular type of extended release formulation of venlafaxine hydrochloride were found to be directly contradicted by unambiguous statements in the body of the specification that an extended release dosage form of venlafaxine hydrochloride was impossible to achieve or fruitless using hydrogel tablet technology (at [99] per Bennett J and [242] per Yates J). It was found that formulations produced by or using such technology were effectively disclaimed as being part of the invention (at [171] per Nicholas J and [247] per Yates J). In both Sigma and AstraZeneca, a significant inconsistency between the priority document and the invention claimed led to a lack of a real and reasonably clear disclosure. But in the case before her Honour (and now before us) there is no such inconsistency.

97    In Fina Research SA v Halliburton Energy Services Inc (No 2) [2003] FCA 251; (2003) 127 FCR 561 (Fina Research SA), a delegate allowed certain amendments to a patent described by Moore J as concerning drilling mud used when drilling for gas and oil. Relevantly for present purposes, the applicant for the patent was successful in seeking to amend the specification to exclude the use of montan wax in several of the claims. The opponent appealed under s 60 of the Act.

98    Justice Moore held that in the circumstances, s 102 of the Act did not render the amendments not allowable. He reached that view for two reasons. First, his Honour found that the complete specification did not suggest montan wax can or ought to be used in the context of explaining and exemplifying both the classes of compounds and certain specified compounds to be used and quantities, including upper limits, to create the claimed invention (at [39]). Secondly, the proposed amendments could be fairly described as a disclaimer and, taking the liberal approach advanced by Tamberlin J in Gambro Pty Ltd v Fresenius Medical Care South East Asia Pty Ltd [1999] FCA 1848; (1999) 48 IPR 625 (at [25]), can be allowed because they do not claim matter not in substance disclosed in the specification.

99    Justice Moore’s reasons for concluding that s 102(2)(b) (read with s 40(3)) was satisfied are contained in the following passage (at [41]):

Applying these principles in the present case, it is difficult to see how the amendments proposed by the respondents could not be viewed as fairly based. The body of the complete specification does not suggest montan wax can or ought be used. The proposed amendments to the claims make it clear that it is not to be used and, to that extent, the monopoly sought in the claims is narrower than that revealed in the body of the specifications. Sections 102(2)(b) and 40(3) do not prevent the amendments being made.

100    The appellant submits that this case does not assist the respondent for the following reasons.

101    First, the appellant submits that the two cases are quite different in that in this case, there is ample expert evidence of the invention disclosed in the Opposed Application and the absence of any basis for excluding from the invention, antiseptic acridines. By contrast, in Fina Research SA, as Moore J said (at [37]):

Beyond the description of that compound in the agreed statement of science and technology which is in general terms, and what might be inferred from Barthel (which does involve the use of montan wax as a viscosifier in a drilling mud), there is no evidence about the significance or otherwise of montan wax not being used or the consequences of it being used if it was. Indeed there was virtually no evidence concerning the science underlying the complete specification.

102    Secondly, the appellant submits that the two cases are quite different in that in Fina Research SA, there was no statement that montan wax was preferred as there is here with antiseptic acridines.

103    Thirdly, the appellant submits that the Barthel patent referred to in the specification in Fina Research SA formed the basis for an exclusion of montan wax and a similar feature is not present in this case.

104    Finally, the appellant submits that insofar that Fina Research SA held that a narrowing of a claim is an allowable amendment by reason of that fact alone, it is inconsistent with AstraZeneca and should not be followed.

105    As I will explain, it seems to me that it is relevant, perhaps highly relevant, in the determination of the not in substance disclosed and fair basis issues that the effect of the amendment is to narrow the scope of a claim, except in those cases where the body of the specification positively recommends the use of the compound, substance or element which it is proposed to exclude by way of amendment. It seems to me that Fina Research SA goes no further than that.

106    The next case to which reference was made is DSI Australia (Holdings) Pty Ltd v Garford Pty Ltd [2013] FCA 132; (2013) 100 IPR 19. It is not necessary to relate the facts of that case. It is sufficient to note that Yates J, in the course of addressing s 40(3) of the Act, said the following (at [240]):

In the present case, Garford submitted that the notional claims propounded by the DSI parties were not fairly based on the matter described in the IRF Application. I am of the view that the notional claims, if they were to be claims of the IRF Application, would be fairly based on the matter described in the specification of that application for the purposes of s 40(3) of the Act. I am satisfied that there is real and reasonably clear disclosure in the body of the specification of the invention that is notionally claimed. Importantly, in this connection, the enquiry as to fair basis is directed to the question of claim width: see, for example, Olin Corporation at 240. A claim may be fairly based for the purposes of s 40(3) of the Act where it adds a feature to a combination otherwise described in the specification and, by that addition, limits the described invention, as a matter of definition, to a more restrictive form than that to which the patentee might otherwise be entitled. In short, a claim may be fairly based for the purposes of s 40(3) of the Act even when all the characteristics by which the invention is defined in the claim are not described in the body of the specification itself, provided those characteristics are truly limiting ones in the sense that I have described.

This passage was cited with approval by Beach J in Meat & Livestock Australia Ltd v Cargill, Inc [2018] FCA 51; (2018) 354 ALR 95 (at [920]). However, the appellant submits that an examination of his Honour’s later decision in Meat & Livestock Australia Ltd v Cargill, Inc (No 2) [2019] FCA 33; (2019) 139 IPR 47 indicates that his Honour’s observations overall do not assist the respondent. His Honour was dealing with an application by the patent applicant to amend under s 105(1A) of the Act. His Honour was required to consider whether the amendments were allowable under s 102 of the Act.

107    The relevant amendment for present purposes was “… and is in linkage disequilibrium with the SNP at position 300 with an r2 value of ≥0.7.

108    Justice Beach said (at [202]):

Second, I agree with MLA that it is not sufficient in and of itself for Branhaven’s success on the amendment application, as Branhaven contends, that the effect of the amendments is to narrow the scope of the matter that is claimed to a subset of what was already disclosed in the 253 Application. Such an approach was rejected by the Full Court in AstraZeneca AB v Apotex Pty Ltd (2014) 226 FCR 324 in relation to section 114(1) at [244]:

A very general description of an invention in a specification before amendment might not contain a real and reasonably clear disclosure of more specific embodiments of the invention subsequently disclosed and claimed after amendment … Whether or not there is a real and reasonably clear disclosure in the specification before amendment of what is claimed in such circumstances is the question that arises in this case.

109    The issue before Beach J was not whether the notion of linkage disequilibrium had been disclosed as clearly it had been. The issue was whether the introduction of the metric and the value was not “in substance disclosed” (at [267]–[268]). His Honour found that the requirements of substantial disclosure and fair basis were satisfied. In two important passages, his Honour said the following (at [272] and [278]):

272    It is apparent that there may be no need for explicit disclosure in the specification of truly limiting features; I am not here dealing with the “very general description of the invention” case of the type discussed by the Full Court in AstraZeneca, and in any event that Court expressed itself in terms of “might not contain” (my emphasis). In the present case the measure of LD and its degree which are being added are truly limiting features and matters of detail to the LD aspect already disclosed.

278    In that context, all that is being done in the proposed amendments is to use a common general knowledge measure of LD to provide an explicit definition of a feature of the invention that is already disclosed (implicitly and explicitly) in the description of the 253 Application: a requirement for LD between a limb (b) SNP and a limb (a) SNP. This involves merely clarifying or claiming a subset of what is already in substance disclosed, and does not result in any lack of fair basis.

110    The way in which the appellant puts the matter is that this case is quite different because there is no disclosure at all of the integer which is sought to be added into the claim as part of the definition of the invention and the description of the specification is quite contrary to that integer.

111    The final of the four first instance decisions is United States Gypsum. The approach of Moshinsky J in that case provides a good example. In that case, the amendments were disallowed by the Commissioner’s delegate but allowed by Moshinsky J on the appeal. The specification concerned a lightweight gypsum board and the amendments in respect of one key feature, namely, a given density range for the board, merely reduced the density range. Moshinsky J said that the amendments did not fall foul of s 102(1) or s 102(2)(b) read with s 40(3). His Honour said (at [44] and [57]):

44    It follows that where the amendments would merely narrow the scope of the invention claimed, they are likely to have been in substance disclosed and fairly based: see, eg, Emperor Sports at [80], [86] per Lindgren J. In other words, a claim that is more limited in scope than the invention as described can be, and perhaps usually will be, fairly based on the description given: see Bodkin C, Patent Law in Australia (2nd ed, Thomson Reuters, 2014) at [5840].

57    In light of the above, I consider that there was a real and reasonably clear disclosure of feature 1 in the specification as filed. In particular, in relation to proposed claims 1, 4, 6 and 39, feature 1 is merely narrowing the density range from the range that was previously claimed. Consistently with Emperor Sports, it is difficult to see how an amendment of this nature was not in substance disclosed by the specification as filed. In relation to proposed claim 8, which claims feature 1 in combination with other claims, on the basis of the evidence of Professor Liu set out in [56](d) and (e) above, which was not contradicted, this proposed claim was in substance disclosed in the specification as filed. Accordingly, neither s 102(1) nor s 102(2)(b) read with s 40(3) presents an obstacle to the requested amendments insofar as they relate to feature 1.

112    By way of summary, I consider that the authorities establish the following propositions with respect to the not in substance disclosed and fair basis issues. First, from start to finish, the test is whether there is a real and reasonably clear disclosure. Secondly, as the survey set out above of some of the many cases in this area illustrates, there are many different circumstances in which questions of amendment arise and it is important that close attention be paid to the particular facts and circumstances. Thirdly, there is no automatic rule that amendments reducing the scope or width of a claim will be held to satisfy the statutory requirements. Fourthly, although there is no automatic rule, amendments reducing the scope or width of a claim will usually satisfy the statutory requirements because they will not travel beyond the matter disclosed in the specification. Fifthly, the Full Court in AstraZeneca provided two examples of cases where the statutory requirements would not be met. They are only examples because the question is (as I have already said) whether there is a real and reasonably clear disclosure.

The Joint Expert Report

113    The experts attended a joint conference and a joint expert report was prepared and became evidence in the trial.

114    The experts were asked to address nine questions. Most of the questions related to the proper construction of relevant parts of the Opposed Application.

115    The Opposed Application uses the term “antiseptic compound” in Claim 1 and in various parts of the body of the specification. The experts agreed that this term refers to a single chemical moiety or a mixture of closely-related chemical moieties which singly and/or together fit the definition of “antiseptic”. The experts agreed that the term “antiseptic compound” is used in the Opposed Application as a grammatical variation of the word “antiseptic”. The experts agreed that suitable definitions of “antiseptic” should be based on definitions found in common veterinary textbooks published on or before the priority date.

116    One suitable definition of “antiseptic” is contained in the international textbook Brander GC, Pugh DM, Bywater RJ and Jenkins WL, Veterinary Applied Pharmacology and Therapeutics (5th ed, Bailliere Tindall, 1991) (Jenkins) and, in particular, in the chapter titled “Disinfectants and Antiseptics” at page 580:

The term “disinfectant” is applied to chemical agents which kill or prevent multiplication of microorganisms, particularly those which cause disease, i.e. bacteria, protozoa, fungi, or viruses. Most disinfectants rapidly kill bacteria (i.e. within minutes), this contrasts with antibiotics which though effective at lower concentrations may be only bacteriostatic or kill only after several hours exposure. Disinfectants are usually applied to inanimate surfaces, since they are often too toxic at the use-concentrations to be applied to the body. Disinfectants which can be applied to the body are usually called antiseptics.

(Emphasis added.)

117    The dictionary, Blood DC and Studdert VP, Saunders Comprehensive Veterinary Dictionary (2nd ed, WB Saunders, 1999) defines “antiseptic” at page 75 as follows:

Antiseptic: 1. preventing sepsis. 2. any substance that inhibits the growth of bacteria, in contrast to a germicide, which kills bacteria outright. Antiseptics are not considered to include antibiotics, which are usually taken internally. The term antiseptic includes disinfectants, although most disinfectants are too strong to be applied to body tissue and are generally used to clean inanimate objects such as floors and equipment. Includes physical antiseptics, chemical antiseptics, halogens, alcohols and surfactants.

118    The American textbook, Boothe DM, Small Animal Clinical Pharmacology and Therapeutics (2nd ed, Saunders, 2001) in the chapter titled “Disinfectants, Antiseptics, and Related Germicides” provides at page 250:

Antiseptic: a substance that prevents or arrests the growth or action of microorganisms on living tissue either by inhibiting their activity or by destroying them.

119    The experts agreed that in the general understanding of the term “antiseptic”, a chemical compound can be referred to as an antiseptic if either it kills microorganisms or if its activity inhibits the replication of microorganisms, when it is safely applied topically to living tissue.

120    The definition of antiseptic in the Opposed Application is set out above (at [21]).

121    There was some disagreement between the experts as to the extent to which the definition of antiseptic in the Opposed Application differed from the general definition of antiseptic. The appellant’s experts (Professors Wainwright, Laven and Whittem) considered that the two definitions differed in that the definition in the Opposed Application referred to the “spreading” of infectious organisms, but not the inhibition of the replication of microorganisms. They understood the spreading of infectious organisms to mean the movement of such organisms from one location to another. In their opinion, the definition in the Opposed Application seemed to omit an explicit inclusion of activity which merely inhibits the replication of microorganisms, except in a case where the inhibition of replication is the mechanism by which the spreading of the microorganisms is prevented.

122    The respondent’s experts (Professors Cook and Huxley and Associate Professor Bunt) considered that the definition of “antiseptic” in the Opposed Application did not differ from the general definition. In their opinion, the reference in the Opposed Application to “any agent that kills or prevents the spreading of infectious organisms” covered antiseptics which both killed and inhibited the replication of microorganisms. In other words, they considered that preventing the spreading of infectious organisms is synonymous with inhibiting the replication of microorganisms. They considered that their view is reinforced by the reference in the definition to “in order to prevent the spread of infections”. They considered that that separately covered the movement of infectious organisms from one location to another, that is, the antiseptic can kill or prevent replication in order to prevent the spread of infections.

123    As the evidence developed, it became clear that nothing turned on this difference of opinion between the experts concerning the general understanding of the word “antiseptic” and the definition of the word “antiseptic” in the Opposed Application.

124    As far as the meaning of the term “antiseptic compound” as used in Claim 1 is concerned, the experts agreed that the term should be read in the same way as they had stated the term should be read as appearing in the Opposed Application. They agreed that Claim 1 allows for the inclusion of more than one antiseptic compound in the claimed formulation and that Claim 6 provides a narrowing constraint of “wherein the antiseptic is in the form of chlorhexidine or salt thereof”.

125    The experts were asked to address what antiseptic compounds or types of antiseptic compounds the Opposed Application discloses as being suitable candidates for use in the claimed composition.

126    The experts agreed that the types and nature of the antiseptics disclosed in the Opposed Application are broad. They agreed that this follows from the fact that in the third passage on page 13 of the Opposed Application, it is said that the use of chlorhexidine should not be seen as limiting, as any other antiseptic with the desired characteristics may be used. The statement of preferred properties in the first passage on page 12 has at the end of each preferred property “and/or” and this could mean, according to all the experts, that an antiseptic does not need to have any of the preferred properties to be included in the Opposed Application. The experts agreed that when it came to formulating the product, some antiseptics would be unsuitable and they gave as examples, gaseous antiseptics, unstable antiseptics or other antiseptics with deleterious properties.

127    All the experts, other than Professor Huxley, agreed that there was a difference between the properties which were desirable and those properties which were essential in the choice of an antiseptic. The experts, other than Professor Huxley, agreed that the Opposed Application does not disclose in the body of the specification or in the claims that the antiseptic has a particular type of chemical structure, mode of action, degree of ionisation or site of action in or on the target organisms.

128    Professor Huxley did not consider it necessary to address this issue, although he said that if he had addressed it, he did not disagree with the unanimous opinion of the other experts. However, he considered the decision on what is included to be arbitrary. Professors Wainwright and Whittem believed that the issue should be addressed because it directly related to the type of antiseptic one would consider as a suitable candidate or otherwise for the claimed formulation.

129    The experts were asked to address what antiseptic compounds, or types of antiseptic compounds, the Opposed Application disclosed as being preferred for use in the claimed composition. With respect to this issue, the experts were divided into three camps.

130    Professor Huxley and Associate Professor Bunt agreed that the Opposed Application disclosed chlorhexidine as the most preferred antiseptic and, in that respect, they referred to Claim 6. They also agreed that the Opposed Application specifically disclosed QACs, for example, cetrimide and benzalkonium chloride, and povidone-iodine as examples of preferred antiseptics. In this connection, they referred to the passage in the Opposed Application which reads:

However, the use of chlorhexidine should not be seen as limiting, as any other antiseptic with the desired characteristics may be utilised with the present invention. Antiseptic with poor absorption characteristics are preferred, these may include, for example ionised antiseptics. For example, quaternary ammonium compounds may be suitable, including, but not limited to Cetrimide and BZK. Similarly povidone iodine which is currently used in the dairy Industry may be suitable[.]

131    The construction favoured by Professor Huxley and Associate Professor Bunt is based on the antiseptic compounds they identified as being the only ones specifically named in the Opposed Application and that these antiseptics are, therefore, those which the applicant identified as preferred during the development process. The experts designated this interpretation as “Interpretation 1”.

132    Professors Wainwright and Whittem advanced a different interpretation. They considered that the Opposed Application disclosed as preferred any antiseptic which is mixed with the barrier material and meets one or more of the preferred criteria as the preferred antiseptic. They pointed to the fact that the individual properties of the preferred antiseptic (other than being capable of being mixed with the barrier material) are identified in two sections in the Opposed Application.

133    First, the individual properties of the preferred antiseptic are identified in the first passage on page 12 of the Opposed Application.

134    Secondly, they referred to the passage on page 13 of the Opposed Application as follows:

Preferably, the antiseptic may be released from the formulation at such a concentration that it provides a localised concentration of antiseptic in the area between the formulation and the side of the teat canal, or/and lower portion of teat cistern which is sufficient to prevent the passage of, kill, or deactivate any micro-organisms that are present in the teat canal or/and lower portion of teat cistern[.]

135    Professors Wainwright and Whittem took the view that the second passage is a restatement of property c) in the list of desirable properties. It will be recalled that property c) is in the following terms:

c)    the antiseptic has a release rate such that the concentration in the aqueous channel is greater than the minimum inhibitory concentration (MIC) for at least 2-4 weeks …

136    Professors Wainwright and Whittem were of the view that a preferred antiseptic compound is simply any antiseptic compound which meets at least one of the six preferred properties and can be mixed with the barrier material, that is, whether an antiseptic has at least one of the preferred properties determines whether it is a preferred antiseptic rather than whether it is named in the Opposed Application. The experts designated this interpretation as “Interpretation 2”.

137    All of the experts agreed that the number of preferred antiseptics using the interpretation advanced by Professors Wainwright and Whittem (Interpretation 2) would be large.

138    Professors Laven and Cook expressed a slight preference for the interpretation advanced by Professor Huxley and Associate Professor Bunt (Interpretation 1), but stated that both interpretations were reasonable given the wording of the Opposed Application.

139    The experts then addressed whether they considered that the Opposed Application discloses that any antiseptic compounds or types of antiseptic compounds are excluded from use in the claimed composition. They agreed that the Opposed Application does not disclose any antiseptic compounds or types of antiseptic compounds to be excluded from the formulation or use in the claimed composition. They agreed that the Opposed Application does identify that the antiseptic compounds or types of antiseptic compounds must be mixable with the barrier material and, in that context, they referred to Claim 1. They agreed that the description of preferred properties of antiseptic compounds and preferred antiseptic compounds as disclosed in the Opposed Application does not exclude any specific antiseptic compounds. I will need to return to this aspect of the joint expert report because it forms the basis of one of the appellant’s primary and most straightforward arguments.

140    The experts were asked to address their understanding of QACs as that term is used in the Opposed Application. They all noted that there was no definition of QACs in the Opposed Application. There was a difference of opinion between the experts as to their understanding of the term as used in the Opposed Application.

141    The respondent’s experts considered that the term “quaternary ammonium compounds” as used in the Opposed Application refers specifically to a commonly used group of disinfectants/antiseptics. In other words, on this view, the term “quaternary ammonium compounds” is used as a noun specifically to name that group and by extension, the commonly used disinfectants it contains. They referred to the fact that when mention of QACs is made in the Opposed Application, it provides “including, but not limited to Cetrimide and BZK”. They noted that cetrimide and BZK are two of the most common members of that group. They also expressed the opinion that the QAC group of disinfectants or antiseptics would not normally be considered to contain acridines.

142    By contrast, Professor Wainwright considered that the term “quaternary ammonium compounds” as used in the Opposed Application refers non-specifically to a wide range of chemicals which have a quaternary ammonium group as part of their chemical structure and have disinfectant or antiseptic properties. In his opinion, the term “quaternary ammonium compounds” is used in the Opposed Application as an adjective to describe an aspect of chemical structure. There are a very large number of chemicals which contain a quaternary ammonium group as part of their chemical structure and some of these chemicals have antiseptic or disinfectant properties and these include some quaternary acridines.

143    The experts were asked to address their understanding of the term “ionised anti-septic” as used in the Opposed Application. They noted that there was no definition of “ionised anti-septic” in the Opposed Application. They noted that the term is said in the Opposed Application to be an example of an antiseptic with poor absorption characteristics, but that no further explanation is provided. They noted that it is not clear from the examples provided in the Opposed Application whether they are exemplars of antiseptics which meet one or more of the following criteria: (1) poor absorption characteristics; (2) ionised antiseptics; and (3) other antiseptics which could be used in the formulation.

144    The experts were asked to address the extent to which, if at all, antiseptic acridines are “quaternary ammonium compounds” as that term is used in the Opposed Application. They agreed that all acridines which are QACs are 100% ionised as cations at all pH values and that the extent of ionisation of acridines which are not QACs will depend on the pH of the environment.

145    The experts agreed that acridines which are antiseptic exist in a highly ionised state and that this is due either to molecular substitution promoting protonation of the acridine ring nitrogen (up to 100% ionised at physiological pH), or to quaternisation of the ring nitrogen (100% ionised, regardless of pH). They agreed that of the antiseptic acridines, those which are quaternised such as euflavine chloride (= purified acriflavine) are QACs using the following rationale. A QAC is a nitrogen-containing compound where the nitrogen is covalently bonded four times to carbon, resulting in a positive charge on this nitrogen. The bonds may be four single bonds, as in BZK or cetrimide, or two single and one double bond as in the ring-containing antiseptics cetylpyridinium chloride and dequalinium chloride. Euflavine chloride (purified acriflavine) also has this characteristic.

146    The experts were asked to explain the extent to which, if at all, antiseptic acridines are “ionised anti-septics” as that term is used in the Opposed Application. The experts agreed the following: (1) it is the ionised, cationic nature of acridines which allows antiseptic activity and non-ionised acridines have little or no activity; (2) all acridines which are QACs are 100% ionised at all pH values; and (3) the extent of ionisation of acridines which are not QACs will depend on the pH of the environment.

147    The experts agreed that in extended studies on many acridine derivatives carried out by Adrien Albert (whose work is discussed further below), it was established that cationic ionisation (positive charge) was required for their effective antiseptic action. Antiseptic acridines are therefore positively ionised antiseptics. Acridines which remain uncharged or are negatively charged show little or no antiseptic action. Albert also established a correlation between the degree of ionisation and antiseptic action, finding that acridines which became positively ionised to a high degree were usually the most active antiseptics. Quaternary antiseptic acridines such as euflavine chloride are 100% ionised.

148    The experts were asked to address the kind(s) of mastitis experienced by cows during the dry period. They agreed that sub-clinical (no obvious clinical signs of disease; most common) and clinical forms (also mild to peracute; rarely) of mastitis (bacterial infection of the mammary gland) are experienced by cows during the dry period. Typically, infections are thought to be acquired during the period at the beginning and end of the dry period, but the infections do not cause clinical mastitis immediately. Clinical mastitis caused by bacteria acquired during the dry period most commonly occur shortly after calving when lactation starts with an incidence peak in the first few days, but can occur up to a number of months later. There is evidence that some of the bacteria causing mastitis in early lactation have entered the mammary gland earlier during the dry period. Finally, some sub-clinical intramammary infections acquired during the previous lactation can be carried into the dry period. The experts agreed that in general, the bacteria that can cause mastitis (sub-clinical and clinical) can be classified into two groups, namely, environmental and contagious. Environmental is where the bacteria are acquired from the environment, that is, the pasture, or the shed etc., and contagious refers to bacteria being cow-associated spreading from cow to cow, most commonly during the milking process, without an obvious environmental reservoir.

149    It is convenient at this point to note the evidence given in the joint session of experts about the size of the classes of antiseptics, ionised antiseptics, QACs and acridines respectively. The evidence is as follows. There are millions of antiseptic compounds which meet the definition in the Opposed Application, both before and after the proposed amendments. There is a large universe of ionised antiseptics. Some acridines are permanently ionised and some are not ionised at all. The ionisation of some acridines depends upon the pH of the environment. There are ionised antiseptics which are acridines and there are ionised antiseptics which are not acridines.

150    There is a large universe of QACs and some of them are antiseptics and some are not. If an acridine is not ionised, it will not be a QAC. Some ionised acridines are QACs and some ionised acridines are not QACs.

151    BZK and cetrimide are QACs, but they are not acridines. There are many QACs which are not acridines. Professor Wainwright was asked to give a rough indication of how many QACs are not acridines. He said that that was difficult to assess, but there were probably thousands of QACs which are not acridines.

152    The experts were asked to identify the species of bacteria which were the major and minor causes of that or those kind(s) of mastitis. The experts agreed that for mastitis during the dry cow period, the actual incidence for individual bacterial species is not known, but is assumed based on the studies in which bacteria were cultured from cases of mastitis either immediately prior to or immediately after the dry period. In most countries, the most frequent bacteria thought to cause new dry period intramammary infections are the “environmental” bacteria streptococcus uberis and coliforms, and there are more streptococcus uberis in pasture-based systems/season (e.g., New Zealand and Australia) and more coliforms in barn-based systems/season (e.g., the United States and Europe). The experts identify the coliform bacteria generally encountered.

153    The experts were asked to address what they understood major and minor causes of bovine mastitis to mean in the context of the Opposed Application. They agreed that major and minor could be interpreted in different ways by different skilled addressees, as influenced by their different skill sets. No one of the following four interpretations was exclusively accepted without question by the majority of the experts. The four interpretations are as follows:

(1)    major could be interpreted to mean the dominant mastitis causing pathogen during the dry cow period. Minor could be interpreted to mean the minor/less prevalent mastitis-causing pathogens during the dry cow period; and/or

(2)    major could be interpreted to mean the major treatment problem i.e., what is the most difficult mastitis-causing pathogen to effectively treat during the dry cow period. A pathogen for which there is no effective treatment would fit this description; and/or

(3)    major and minor could be interpreted based on the standard mastitis nomenclature which classifies pathogens based on their importance (prevalence and disease severity) in both the lactating cow and during the dry period; and/or

(4)    major and minor could be interpreted from an industry perspective, where they would refer to those pathogens that cause the dairy cow industry the greatest and least financial loss.

154    Professor Whittem did not agree that the third option would be acceptable to any skilled addressee because, in his opinion, this definition of major and minor as commonly described in textbooks and other publications relates to all pathogens identified as causing mastitis in both the lactating cow and during the dry period, while this question and the Opposed Application relate only to mastitis that is experienced during the dry cow period. Professor Whittem held the opinion that this is an important distinction within the consideration of the Opposed Application because products aimed at prevention or treatment of mastitis in lactating cows versus those for dry cows differ markedly.

155    Professors Laven and Huxley disagreed that the third interpretation would not be acceptable to any skilled addressee, as asserted by Professor Whittem. They considered that the use of “Major Pathogens” and “Minor Pathogens” as nouns to describe two groups of mastitis pathogens was widely accepted standard nomenclature amongst those working in the mastitis field before the disclosure date. The standard nomenclature made no differentiation between when major and minor pathogens were either acquired or caused disease. In addition, the mastitis research science at the time was demonstrating significant connections between the dry and lactating periods, meaning they could not be considered independently when studying disease control.

The Person Skilled in the Art or the Skilled Addressee

156    The person skilled in the art or the skilled addressee is the person to whom the specification is addressed. The specification may be addressed to a person or persons with a number of skills and the skilled addressee may comprise a team of persons (Aktiebolaget Hässle v Alphapharm Pty Ltd [2002] HCA 59; (2002) 212 CLR 411 at [30] per Gleeson CJ, Gaudron, Gummow and Hayne JJ; at [153] per Kirby J). It is not in dispute in this case that the Opposed Application is addressed to a number of persons with different skills. The dispute is as to the composition of the notional skilled team. The composition of the notional skilled team may vary depending on the issue being addressed (Birss C (ed), Terrell on the Law of Patents (19th ed, Sweet & Maxwell, 2020) Chapter 8 at [8–77] et seq.).

157    The respondent’s case is that the skilled team would comprise, at least, persons with skills and expertise in the following areas:

(1)    Pharmacology or formulation so as to be able to make the formulation in accordance with the claimed invention;

(2)    Veterinary science, including experience in conducting experiments on animals and methods of administering a formulation to a cow. Professor Huxley said that this field of expertise involves a person with practical experience in animal experimental work to replicate the studies reported in the Opposed Application; and

(3)    Microbiology with a particular knowledge of mastitis and the bacteria which cause mastitis and an understanding of processes such as minimum inhibitory concentrations, or knowledge in microbiology. Professor Huxley said that it is possible that the person with skills and expertise in veterinary science may also have the required level of knowledge of microbiology.

158    The appellant’s case is that persons with skills and expertise in these three areas would be part of the skilled team, but its case is that the third expert (or perhaps a fourth expert) with expertise in antimicrobial compounds or antiseptics would also be part of the skilled team. That person may be a medicinal chemist or another person with expertise in antiseptics.

159    The respondent’s case is that a medicinal chemist would only be part of the skilled team if there was a need to develop new chemicals or new molecules which is the field of synthetic medicinal chemistry and, in the case of the Opposed Application, there is no need for such a person. The skilled team defined by the three areas referred to above would consider first, and have a strong preference for, existing antiseptics which had a proven safety record and were commercially available. Chlorhexidine was an antiseptic with a proven safety record and it had already been used in veterinary products for similar purposes and for human products.

160    In support of its case that the skilled team would include a person with expertise in antimicrobial compounds or antiseptics, the appellant relies on three main arguments. First, the appellant submits that the Opposed Application is not limited to existing antiseptics, whether they are named in the Opposed Application or not. There is a role in the skilled team for a person with skills and expertise in the identification of antiseptics and their properties, including whether they have poor absorption characteristics, such as ionised antiseptics and QACs. Secondly, the appellant submits that Claim 6 of the Opposed Application, which restricts the antiseptic to chlorhexidine or a salt thereof, cannot dictate the composition of the skilled team. I note that there can be different skilled teams for different claims (Alphapharm Pty Ltd v H Lundbeck A/S [2008] FCA 559; (2008) 76 IPR 618 at [200] per Lindgren J). It is true that Claim 6 cannot dictate the composition of the skilled team (Aspirating IP Ltd v Vision Systems Ltd [2010] FCA 1061; (2010) 88 IPR 52 at [110]), but ultimately, I do not think the respondent put this argument. Thirdly, the appellant submits that the premise of the respondent’s argument that a medicinal chemist would only be part of the skilled team where the discovery and formulation of new active compounds is under consideration is incorrect. The fields of medicinal chemistry and antimicrobial chemotherapy, and the expertise in antiseptics that those fields involve, include the identification and development of new uses of existing active compounds and the consideration of the properties of both new and existing compounds and their suitability for a particular application. As to this third matter, I accept that a person with expertise in antiseptics would be part of the skilled team in the case of not only new compounds, but also existing compounds being considered for new uses. However, it was not established that a person with expertise in antiseptics would be necessary in the case of existing antiseptics with known properties, a proven safety record and prior use in the relevant field, or a closely related field. I accept Professor Cook’s evidence that in such a case, any issues as to interactions between compounds could be dealt with by a pharmacist or formulation chemist.

161    At one level, it seems to me that the appellant’s argument is correct. The definition of “antiseptic” in the Opposed Application is very wide and includes new compounds and existing compounds developed for new uses. If one stops at that point, then a person with expertise in antiseptics is a member of the skilled team. The appellant said that the Court should stop at that point and that the respondent’s arguments to the contrary are flawed because they are based on how its skilled team would implement the invention and that is not the correct question.

162    Professor Cook said that the named antiseptics of chlorhexidine, cetrimide, BZK and povidone-iodine have been used for a “very, very long time” and with very little toxicity risk to humans. In particular, chlorhexidine is an antiseptic known not to cause toxicity problems, has good potency and there is no resistance to it. Professor Cook said that it is known that chlorhexidine, cetrimide, BZK and povidone-iodine are not mutagenic or cancer-causing or cytotoxic and a medicinal chemist is not required to address those issues as he or she would be in the case of the formulation of new compounds. That meant, in Professor Cook’s opinion, that chlorhexidine was the number one choice as the antiseptic followed by QACs, such as cetrimide and BZK. He did not consider that a medicinal chemist was absolutely essential because, in his experience, they are normally involved in synthesising new chemical entities. As I understand Professor Cook’s evidence, a medicinal chemist would be included in the skilled team if the existing team decided to implement the invention by including a new chemical entity as the antiseptic. As I have said, Professor Cook considered that a formulation chemist or pharmacologist could carry out the task of formulating different forms of a known antiseptic. Both Professors Cook and Huxley would not look beyond chlorhexidine and the other named antiseptics, particularly in circumstances in which the formulation is to be used in food-producing animals.

163    Professor Whittem agreed that on reading the Opposed Application, he would have considered any antimicrobial compound approved for veterinary use as a potential candidate for use in the claimed formulation, but he would have directed his attention to the use of existing chemicals and that he would not have looked for new molecules.

164    Professor Laven said that he would have chosen chlorhexidine as the antiseptic to be used in the formulation, but at the same time he said that the Opposed Application does not exclude from consideration other antiseptics, even antiseptics which do not meet any of the preferred properties. Professors Laven and Whittem said that new compounds involve greater time, money and risk in the case of products which are to become part of the human food chain as do existing compounds that have not had another use in a food animal product. Professor Laven also said in the course of the joint session of experts that it would be “stupid” to start afresh and look for some brand-new compound that has never been used in veterinary science.

165    All of the experts agreed that they would look first at the use of an existing compound for the very good reasons that that would reduce the cost and development time in the case of a compound to be used in a food-producing animal and in circumstances where there were existing antiseptics with proven safety records. Each of chlorhexidine, cetrimide, BZK and povidone-iodine were well-known and widely-used antiseptics at the priority date.

166    The question is whether the notional skilled team would include an expert in antimicrobial compounds or antiseptics. Each side advanced persuasive arguments in support of its answer to that question. Not without some hesitation, I have concluded that an expert in antimicrobial compounds or antiseptics would be included in the notional skilled team. All of the experts said that chlorhexidine would be the first choice as the antiseptic compound with other existing compounds following. Professor Cook said that an expert in antimicrobial compounds or antiseptics would be part of the skilled team if a new compound was under consideration. Professor Huxley accepted that such a person would be part of the skilled team if consideration was being given to antiseptics other than those named in the Opposed Application. The test is the person or persons to whom the Opposed Application is addressed or, put another way, the skilled team is to be assembled having regard to the invention described and claimed in the Opposed Application. The invention described and claimed includes a very large number of antiseptics and, in those circumstances, I consider that an expert in antimicrobial compounds or antiseptics would be part of the skilled team, even if, in the result, the invention is likely to be carried out without calling on the skills of such a person.

167    The resolution of this issue is not decisive because of the findings I make as to the extent of common general knowledge about acridines, antiseptic acridines and acriflavine.

168    Related to this last point is the respondent’s submission that even if the skilled team would include an expert in antimicrobial chemotherapy or a medicinal chemist, it would not be an expert with the skills and expertise of Professor Wainwright and, in particular, his extensive knowledge and work with acridines. I consider that that submission is correct.

169    It is convenient to repeat and summarise in more detail the particular skills and experience of Professor Wainwright. In his research, Professor Wainwright has focused on medicinal chemistry and, in particular, antimicrobial synthesis and testing. He has over 30 years’ experience in antimicrobial chemotherapy involving both academic and industrial settings. Chemotherapy involves the use of chemicals for therapy and the treatment of all types of infections or conditions using chemicals. Professor Wainwright’s experience is specifically related to the identification, synthesis and study of antimicrobial compounds which have activity against microbial organisms, including bacteria, fungi, viruses and protozoa. Professor Wainwright has, and continues to be, consulted on projects which relate to the light-activation of suitable antimicrobial compounds to increase their effectiveness against target pathogens. Professor Wainwright has written in excess of 120 papers in the field of antimicrobial chemotherapy and he has developed specialised knowledge in that field.

170    The synthesising of compounds means the creation of complex or new chemical compounds from simpler or existing compounds. Professor Wainwright has synthesised close to 1,000 compounds over 30 years and that is an area of particular interest to him. Relatedly, he identifies and develops new uses for existing compounds. When he refers to new uses of existing compounds, Professor Wainwright is referring to a particular focus of his professional career being the photosensitising or light activation of compounds.

171    Professor Wainwright said that it is always preferable to use a known chemical entity that has previously received approval as an antiseptic and that there is nothing in the Opposed Application to suggest to the skilled team that they should synthesise a new compound.

172    Professor Wainwright has “considerable” expertise in acridines and, when it was put to him, he agreed that he could be considered “something of a world expert in acridines”. He attached a long list of publications to his first affidavit and he agreed that many of them dealt with the topic of acridines. He published articles about acridines in 1997, 1998 and three articles in 2001. He said that his aim in some of these articles was to remind the scientific community that, although seen by many as obsolete and forgotten, acridines were useful. He agreed that his aim in publishing the articles was to remind the scientific community of these “forgotten antiseptics”.

173    Professor Wainwright gave evidence that when reading the Opposed Application, he immediately identified antiseptic acridines, such as acriflavine, as examples of ionised antiseptics and QACs for use in the claimed composition. In his oral evidence, he agreed that this was because he has worked for a very long time with acridines, “so it was an obvious answer for him.

174    Professor Wainwright agreed with the following: (1) none of the articles he wrote about acridines, or lectures he delivered about acridines, suggested their use in veterinary medicine; (2) he has never been involved in developing a veterinary product, he is not a formulation scientist and prior to 17 September 2008, he had no experience in the prevention or treatment of bovine mastitis; (3) he has never been consulted about the formulation of a teat seal for bovine mastitis and he accepted that it is unlikely that as at September 2008 he would have been consulted by anyone in Australia about formulating a teat seal; and (4) his expertise is generally aimed at hospital-type bacteria which are resistant.

175    Associate Professor Bunt deferred to Professor Wainwright’s expertise in the identification of acridines and, when asked about the ionisation of acridines, Professor Huxley referred to Professor Wainwright as one of the “world’s experts”.

Common General Knowledge at the Priority Date

176    The Opposed Application does not expressly refer to acridines, or to particular types of acridines, such as acriflavine or euflavine. They are not identified by name as preferred antiseptics. The respondent contends that they would not be understood by the skilled addressee as preferred antiseptics because they are not named. Alternatively, the respondent contends that they would not be understood by the skilled addressee as preferred antiseptics unless it was common general knowledge that they had one or more of the preferred properties identified in the first passage on page 12 or were, or at least some of them were, ionised antiseptics or QACs. If that was not common general knowledge, then, on the respondent’s case, acridines are not preferred antiseptics within the terms of the Opposed Application.

177    It is necessary to identify the common general knowledge shortly before the prior date which the skilled addressee would have for the purposes of construing the Opposed Application. In determining the content of common general knowledge, it is necessary to examine the position shortly before the priority date. That is because it is possible for information to have been common general knowledge at a point in time before the priority date, but to have ceased to have been so at the priority date. By the time of the priority date, the information may “have been discredited or forgotten or merely ignored” (Birss C (ed), Terrell on the Law of Patents (19th ed, Sweet & Maxwell, 2020) at [8–77]; Martin Engineering Co v Trison Holdings Pty Ltd [1989] FCA 64; (1989) 14 IPR 330 (Martin Engineering) at 350 per Burchett J; Technological Resources Pty Ltd v Tettman [2019] FCA 1889; (2019) 375 ALR 185 at [48]–[49] per Jagot J).

178    The starting point in terms of the identification of information which constitutes common general knowledge is the description of the concept in the reasons for judgment of Aickin J in Minnesota Mining and Manufacturing Co v Beiersdorf (Australia) Ltd [1980] HCA 9; (1980) 144 CLR 253 (at 292):

[T]hat which is known or used by those in the relevant trade. It forms the background knowledge and experience which is available to all in the trade in considering the making of new products, or the making of improvements in old, and it must be treated as being used by an individual as a general body of knowledge.

179    A critical feature of common general knowledge is that it is known to, and accepted by all or the bulk of those in the trade (British Acoustic Films Ltd v Nettlefold Productions Ltd (1935) 53 RPC 221 (British Acoustic Films) at 250 per Luxmoore J; Graham Hart (1971) Pty Ltd v S W Hart & Co Pty Ltd [1978] HCA 61; (1978) 141 CLR 305 at 329 per Aickin J (with whom Barwick CJ agreed); Aktiebolaget Hässle v Alphapharm Pty Ltd [1999] FCA 628; (1999) 44 IPR 593 at [39] per Lehane J; Ranbaxy Laboratories Ltd v AstraZeneca AB [2013] FCA 368; (2013) 101 IPR 11 at [217] per Middleton J). With respect, a clear statement of this feature of common general knowledge was made by the Full Court of this Court in Idenix as follows (at [192]):

It is necessary for us to observe at this point that common general knowledge is background knowledge and experience which is available to all in the trade. It must be generally accepted and assimilated by persons skilled in the art and known and accepted without question by the bulk of those who are engaged in the particular art. Information is not common general knowledge merely because it might be found in a journal, even if widely read. In that conceptual framework, the primary judge correctly found that the hypothetical skilled addressee should not be treated as having available, as part of the common general knowledge, all of the very specific expertise and experience in the fluorination of nucleosides or carbocyclic compounds that Professor Meier and Dr Borthwick possessed by reason of their involvement in particular projects

180    It follows that the fact that a witness, or even a number of witnesses, had knowledge at the priority date does not of itself establish that the knowledge was common knowledge. The witness may be an expert who has specialised expertise and knowledge (British Acoustic Films at 250 per Luxmoore J; Idenix at [192]). At the same time, as the respondent pointed out, evidence that an expert, or a number of experts, were not aware of certain information may be evidence, possibly powerful evidence depending on the circumstances, that the information was not common general knowledge (Martin Engineering at 350 per Burchett J).

181    Common general knowledge and public knowledge are not the same. The requirement that information be accepted or assimilated by all or the bulk of those engaged in the relevant art before it can be considered to be common general knowledge means that proof that an article or journal has been widely circulated, or even widely read, is not of itself sufficient to establish that it is common general knowledge. In British Acoustic Films, Luxmoore J said (at 250):

In my judgment it is not sufficient to prove common general knowledge that a particular disclosure is made in an article, or series of articles, in a scientific journal, no matter how wide the circulation of that journal may be, in the absence of any evidence that the disclosure is accepted generally by those who are engaged in the art to which the disclosure relates. A piece of particular knowledge as disclosed in a scientific paper does not become common general knowledge merely because it is widely read, and still less because it is widely circulated. Such a piece of knowledge only becomes general knowledge when it is generally known and accepted without question by the bulk of those who are engaged in a particular art; in other words, when it becomes part of their common stock of knowledge relating to the art.

182    I turn now to identify the matters of common general knowledge shortly before the priority date of 17 September 2008 established by the evidence in this case.

183    As a general proposition, I bear in mind, as the appellant pointed out, that, in assessing the evidence of the experts about acridines and their properties, substantial parts of the evidence of Professors Cook and Huxley and Associate Professor Bunt was based on information and knowledge they acquired after the priority date.

184    As I have said, in the substantive opposition proceeding, the delegate found that it was part of the common general knowledge at the priority date that acriflavine had an antiseptic property and was a dye (at [198] and [207]). The respondent did not appeal against the delegate’s decision in the substantive opposition proceeding. Instead, it chose to make an application to amend the claims. The appellant submits that there is clear authority that, in those circumstances, it is not open to the respondent in subsequent opposition proceeding to challenge a final decision on issues arising in the first opposition proceeding and the position must be even stronger in the case where the subsequent proceeding is an application to amend the specification.

185    In support of its argument, the appellant relied on the decision of Rares J in Merck, Sharpe & Dohme (Australia) Pty Ltd v Genentech Inc [2016] FCA 324; (2016) 118 IPR 498 (at [55] and [70]) and, in particular, his Honour’s reference to R v Smith; Ex parte Mole Engineering Pty Ltd [1981] HCA 25; (1981) 147 CLR 340 (Mole Engineering) (at 348 per Mason J (as his Honour then was); at 358 per Wilson J). Rares J said (at [70]):

Merck’s challenge to the second decision asserting lack of novelty and inventive step was in reality an attack on the first decision that allowed Genetech [sic] to amend claims 1, 4, 5, 15 and 28 to overcome the delegate’s findings that they lacked novelty. The attack in the notice of appeal had to be made against the first decision. It could not be made against the second decision by reason of the principle in Mole Engineering and, accordingly, the appeal is incompetent. The delegate’s reasoning in the second decision (assuming she had power to make it) was correct.

(Citation omitted.)

The principle in Mole Engineering is that there is to be one substantive opposition proceeding leading to one decision and it is not possible to have potentially two conflicting decisions with no statutory provision to indicate which decision prevails.

186    In the alternative, the appellant submits that the finding of the delegate was legally indispensable and necessary to his decision and there is an issue estoppel between the parties of the type identified by Dixon J (as his Honour then was) in Blair v Curran [1939] HCA 23; (1939) 62 CLR 464 (at 532) and by Barwick CJ in Ramsay v Pigram [1968] HCA 34; (1968) 118 CLR 271 (at 276). The appellant submits that an issue estoppel arises because, although the delegate is not a court, he had jurisdiction to decide finally a question arising between the parties (Kuligowski v Metrobus [2004] HCA 34; (2004) 220 CLR 363 at [22]).

187    The respondent’s response to the appellant’s submissions is as follows. First, it accepts that when the substantive opposition proceeding resumes after the determination of the amendment application, the findings in the first proceeding will be binding as between the parties. However, there is no authority to the effect that they are binding in this proceeding which is a hearing de novo. Secondly, it submits that there is doubt in the case law as to whether an issue estoppel arises in administrative proceedings dealing with patent validity (SNF (Australia) Pty Ltd v Ciba Speciality Chemicals Water Treatments Ltd [2016] APO 8 at [33]–[46]).

188    The respondent’s acceptance that the delegate’s finding in the substantive opposition proceeding (in respect of which there was no appeal) is binding on the parties when the matter is returned to the delegate for finalisation of those proceedings is important because it is difficult to conceive of a reason why it is not binding at the intermediate stage (i.e., the amendment application). In my opinion, the finding is binding on the parties and it is not to the point that this proceeding is a rehearing before the Court. The point is that it is not an appeal from the substantive opposition decision.

189    I turn now to describe, in summary form, the respective cases of the parties as to the information which comprised common general knowledge at the priority date. I will then set out my conclusions.

190    The appellant conveniently divided its analysis into six topics.

191    First, the appellant identified common general knowledge with respect to antibiotics and antiseptics shortly before the priority date. It referred to the definition of “antiseptic compound” adopted by the experts in the joint expert report. An “antiseptic compound” is a single chemical moiety or a mixture of closely-related chemical moieties which singly and/or together fit the definition of “antiseptic”. A chemical compound can be referred to as an antiseptic if either it kills microorganisms or if its activity inhibits the replication of microorganisms, when it is safely applied topically to living tissue. I accept that these matters were common general knowledge shortly before the priority date.

192    Secondly, the appellant identified its case as to common general knowledge with respect to Gram-positive and Gram-negative bacteria and broad spectrum antiseptics. Bacteria are generally classified as Gram-positive or Gram-negative. The strict definition of the term “broad spectrum” is that it refers to an antimicrobial compound which is effective against some species of both Gram-positive and Gram-negative bacteria. The term “broad spectrum” is commonly used to describe an antimicrobial compound that is effective against a wide range of disease causing bacteria, while “narrow spectrum” is commonly used to describe an antimicrobial compound which is effective against only a specific group of bacteria. I accept that these matters were common general knowledge shortly before the priority date.

193    Thirdly, the appellant identified its case as to common general knowledge with respect to QACs as follows. A QAC is a permanently positively charged organic nitrogen compound in which the nitrogen atom makes four covalent bonds. Such a compound is an ionised compound. I accept that these matters were common general knowledge shortly before the priority date.

194    Fourthly, the appellant identified its case as to common general knowledge with respect to particular antiseptics that were known shortly before the priority date as follows. Before September 2008, known antiseptics included BZK, cetrimide, chlorhexidine, iodophors, triclosan and antiseptic acridines. The MIMS New Zealand 2008 IVS Annual contains a list of chemotherapeutic agents used in veterinary pharmacology. The term “chemotherapeutic agent” refers to any chemical used for the treatment of disease. The list of antiseptics and disinfectants in MIMS New Zealand includes acriflavine, aminacrine (also known as 9-aminoacridine), chlorhexidine and iodophorm (also referred to as iodophors).

195    I accept that known antiseptics shortly before the priority date included BZK, cetrimide, chlorhexidine, iodophors and triclosan. I will return to the issue of the extent to which antiseptic acridines were known antiseptics. MIMS New Zealand contains the matters identified by the appellant.

196    Fifthly, the appellant’s case as to the extent of common general knowledge shortly before the priority date with respect to acridines is as follows.

197    Professor Wainwright gave evidence that acridines comprise a central pyridine ring fused to two benzene rings. He gave evidence that the term “acridines” includes acridine derivatives, which are acridines that have substituted, that is, at least one hydrogen atom bonded to a carbon atom on the acridine ring has been replaced by a different atom or group. Not all acridine derivatives are antiseptics. The antiseptic activity of an acridine derivative is dictated by the position and nature of the substituted group(s) on the acridine core.

198    It was agreed in the joint expert report that antiseptic acridines exist in a highly positively ionised (cationic) state and it is the cationic state of antiseptic acridines which allows antiseptic activity. Further, there is a correlation between the degree of ionisation and antiseptic action.

199    Professor Wainwright gave evidence that the ionisation of acridines at physiological pH was well understood and that the ionisation of acridine derivatives was able to be predicted easily using well-known principles of chemistry before the priority date. He gave evidence that euflavine, proflavine, sinflavin and 9-aminoacridine are examples of antiseptic acridines. Acriflavine is also an acridine. Acriflavine is a mixture of euflavine chloride and a minor amount of proflavine hydrochloride.

200    It was agreed in the joint expert report that antiseptic acridines such as euflavine chloride, the purified form of acriflavine, are QACs, which comprise antiseptic acridines where the ring nitrogen makes four covalent bonds. In addition, all acridines which are QACs are permanently positively charged and so are 100% ionised as cations at all pH values.

201    Professor Wainwright said that euflavine, proflavine and aminacrine have broad spectrum activity in that they have activity against both Gram-positive and Gram-negative bacteria. Acriflavine also has broad spectrum activity, being bactericidal against both Gram-positive staphylococcus aureus and Gram-negative escherichia coli.

202    The appellant’s case is that the evidence establishes that antiseptic acridines have been used in veterinary products and it referred to the following.

203    The first item of evidence is evidence of Professor Wainwright to the effect that ethacridine, euflavine and acriflavine have been used in the treatment of streptococcal mastitis in cows by injection of a solution into the teat canals of cows. To support that proposition, Professor Wainwright referred to the textbook, Albert A, The Acridines: Their Preparation, Physical, Chemical, and Biological Properties and Uses (2nd ed, Edward Arnold, 1966) (Albert). An extract from Albert was in evidence and it contains the following passage:

Nevertheless, ethacridine has been found useful in streptococcal mammitis and mastitis in cows, a solution being injected into the teat-canals either alone (Bugge, 1924) or mixed with a nitroacrdine (14.3) to form ‘Entozon’ Compound Granules (Gerke, 1935; Trautwein, et al., 1934; Schalm, 1942) (for the chemistry of ‘Entozon’ see Section 14.2). However, Steck (1934, 1937) who compared ‘Rivanol’ with euflavine, preferred the latter for bovine mastitis.

204    The second item of evidence is evidence of Professor Whittem to the effect that acriflavine has been used to treat the very delicate gill tissues of fish which are sensitive to irritation. Professor Whittem said:

Finally, with respect to the acriflavines in particular and the question of how irritants would I expect them to be, as a pharmacologist, I’ve used these products in treating fish. They’re marketed in Australia for that purpose. They’re used for treating fungal infections on – or fin rot on fish. So you add the acriflavine to the fish water, and that’s in – in the tank, and they swim around in the tank. The very – one of the very most sensitive tissues of fish are their gills. These are very, very delicate tissues which are where the oxygen and other gases are exchanged with the water. The gills are particularly sensitive to irritation, particularly sensitive to irritation from ammonium ions. In fact, if your fish filter, fish tank filter fails, it’s very often the ammonium ions that cause the fish to die, and yet we use acriflavine in fish tanks.

205    The third item of evidence is also evidence of Professor Whittem. He said that acriflavine has also been used in wound dressing, against staphylococcus aureus, which is one of the pathogens implicated in mastitis:

MR HEEREY: Yes. And there’s description of acriflavine that continues for the rest of that page, and then there’s a heading which says Actions and Uses. And it says that acriflavine is often preferred for wound dressing. And, simply, you would accept that wound dressing is a very different application to the use of an antiseptic for an internal teat seal. Do you accept that, Professor Whittem?

PROF WHITTEM: No, I don’t, because you use an antiseptic, a disinfectant, or an antimicrobial compound, no matter what you want to call it, against the pathogens that you’re targeting. The most common pathogen that infects wounds is staphylococcus aureus, which is a commensal of the skin and, in my mind, one of the target bacteria for treating dry cow mastitis, or preventing dry cow mastitis, is the same organism, staphylococcus aureus. So, in my mind, we’re choosing an antiseptic on the basis of a known ability to target the pathogen of interest.

206    The fourth item of evidence relates to two products containing acridines which were listed in the MIMS Australia 2008 IVS Annual. They are Yellow Lotion and Septicide Cream.

207    MIMS Australia identifies the registered name of Yellow Lotion as Ranvet’s Yellow Lotion Antiseptic Astringent Wound Lotion. The composition contains acriflavine. The indications are stated as follows:

Promotes healing in granulating wounds and helps stop the formation of proud flesh. It promotes a dry surface, resistant to infection without forming an undesirable hard crust on the wound. Has a sedative effect on nerve ends making it a suitable treatment for wounds, cuts and abrasions. Yellow Lotion has a soothing astringent action for treating sprains and bruises, especially for tendons.

208    Professor Whittem gave evidence that he was aware that Yellow Lotion had been used for the treatment of wounds on the udder. He agreed in the course of his evidence that there was nothing in MIMS Australia to indicate that the Yellow Lotion product or acriflavine was suitable for use in the treatment of mastitis.

209    Septicide Cream is referred to in MIMS Australia as being produced by Virbac (Australia) Pty Limited and it is stated that its composition includes proflavine hemisulfate. In another publication in evidence, Septicide Cream is indicated for insect repellent and an antiseptic cream for use on wounds in dogs and horses. Professor Huxley agreed in the course of his evidence that Septicide Cream was approved for use in animals and that could include animals (i.e., horses) that were intended to enter the food chain, subject to a requirement that there be a withholding period of 28 days.

210    The appellant also referred to the fact that in the substantive opposition proceeding, the delegate found that the prior art disclosed veterinary compositions for treating mastitis in dry cows that included acriflavine. That is correct. The appellant submitted that that was consistent with the evidence of the veterinary scientists in the proceeding and it referred to the evidence of Professors Laven and Whittem and Associate Professor Bunt.

211    Professor Laven said that his main exposure to acriflavines in veterinary medicine was their use as a disinfectant or a pigment or a preservative in a teat sealing product. He said that the very first teat sealing product had both bismuth and acriflavine listed as active ingredients. He was asked whether he was referring to a paper published by Dr WJ Meaney in 1977. He said that it was a “bit before” the paper by Dr Meaney because Dr Meaney had just used a product that was commercially available. Dr Meaney had taken a teat seal which had been developed as a method for controlling mastitis and he tested it. Prior to 2008, the only disinfectant that had been used in a bismuth-based teat sealant was acriflavine. Professor Laven said that he had never used it for the prevention of mastitis, but he knew it to be effective, at least as a teat sealant.

212    The paper by Dr Meaney in 1977 was published in the Irish Journal of Agricultural Research (Vol 16, No 3, 1977) and it reported on Dr Meaney’s observations of experiments concerning intramammary teat seals used during the dry period. One seal involved a composition of bismuth subnitrate 25% (w/w) and acriflavine 0.075% (w/w). Professor Laven said that there were three potential reasons why a person might use acriflavine. They are first, as an antiseptic, secondly, as a preservative, and thirdly, because it is orange in colour. Professor Laven said that he did not know, and he did not make any inquiries in 2001, which was at about the time he first read Dr Meaney’s 1977 paper, as to why acriflavine was present in the teat seal. Professor Laven said:

However, it does show that if you make a teat sealant with bismuth and acriflavine it does not cause the cow significant harm or discomfort. So, yes, so to me it shows that you can have a teat sealant with bismuth and acriflavine.

213    Professor Whittem made a statutory declaration in the opposition filed by Pfizer, Inc to New Zealand Patent Application No 571347 on 13 December 2011 and in that document he identified what he considered to be common general knowledge before the priority date. He agreed that he did not expressly identify acridines or acriflavine as part of the common general knowledge. However, he did identify the Meaney 1977 paper as part of the common general knowledge and in his evidence he identified a history of acriflavine being incorporated in a teat seal and not causing toxicity issues. In that connection, he referred to a study in evidence “which showed that acriflavine when incorporated in teat seal at 0.1 per cent was able to leach out of the formulation and kill mastitis causing bacteria”.

214    Associate Professor Bunt was aware of the use of acriflavine in teat seals because he was aware of a UK Patent Application GB2,273,441 (published on 22 June 1999).

215    The appellant’s case as to common general knowledge with respect to mastitis before the priority date is based on the joint expert report. Mastitis is the bacterial infection of a cow’s mammary gland. During the dry period, that is, when they are not milked, cows may suffer sub-clinical and clinical forms of mastitis. Typically, infections are thought to be acquired during the period at the beginning and end of the dry period. Clinical mastitis caused by bacteria acquired during the dry period most commonly occurs shortly after calving, but can occur up to a number of months later. There is evidence that some of the bacteria causing mastitis in early lactation have entered the mammary gland earlier during the dry period. Finally, some sub-clinical intramammary infections acquired during the previous lactation can be carried into the dry period. In Australia and New Zealand, where cow milking and calving are seasonal and pasture-based, streptococcus uberis and staphylococcus aureus are the most frequent and dominant causes of mastitis reported in the dry period. In countries with a barn-based season (such as the United States or Europe), streptococcus uberis and coliform bacteria are the dominant groups of mastitis-causing bacteria. Both streptococcus uberis and staphylococcus aureus are Gram-positive bacteria.

216    I turn now to the respondent’s case as to the content of common general knowledge shortly before the priority date. It is quite different from the appellant’s case.

217    Acridines were not common general knowledge. If they had been at one point in time, they were forgotten and obsolete by the priority date. The antiseptic properties of at least some acridines were not common general knowledge, nor were their characteristics common general knowledge such that they would be identified as ionised antiseptics or QACs. The use of acriflavine in a teat seal was not part of common general knowledge.

218    Each of chlorhexidine, cetrimide, BZK and povidone-iodine were well-known and widely-used antiseptics. The evidence did not establish that it was common general knowledge at the priority date that any acridines were ionised antiseptics or QACs. Professor Huxley is not familiar with acridines or what they are used for. He does not know whether acridines are ionised compounds and whether acridines are QACs without consulting appropriate reference materials. Associate Professor Bunt said that before the priority date, he did not know whether or not acridines were ionised antiseptics. Professor Cook was aware of a single ionised acridine (acridine orange), but he did not consider it to be an antiseptic.

219    As I have said, with respect to knowledge of acridines, the respondent’s case is that before the priority date, acridines were a class of largely forgotten and rarely used antiseptics. The characteristics and potential suitability of acridines did not form any part of the common general knowledge of the notional skilled team and the appellant has failed (so the respondent contends) to identify any expert in Australia with expertise in acridines, far less that any such expert who would have formed any part of the notional skilled team.

220    Professor Cook gave evidence to the following effect. He had never used or considered the use of any acridine as an antiseptic and it would not have occurred to him to use an acridine as an antiseptic in the claimed invention. He was not familiar with acriflavine. In his 27 years as a microbiologist, he has never used any acridine for any purpose and, in particular, he has never used, or considered using, any acridine as an antimicrobial. Before the priority date, he would have regarded antiseptic acridines as peripheral to the claimed invention, if not completely irrelevant, because there were many superior antiseptics available. At the priority date, antiseptic acridines were chiefly of historical interest.

221    Professor Huxley gave evidence to the following effect. He did not know what an acridine is. He would not have thought of acridines when reading “antiseptic” in the claim before amendment. He was not aware of any studies which have used acridines in cattle since 1942 and acridines have not commonly been used as antiseptics in the veterinary field in more recent times. In oral evidence, Professor Huxley said that he had never heard of acriflavine being used in dairy cows anywhere in the world. He had not come across any products containing acriflavine being commonly used in dairy cattle at the priority date. Professor Huxley described the field of the invention as dairy cow veterinary medicine (with aspects of pharmacology) and, more particularly, the prevention of bovine mastitis. He produced eight common veterinary textbooks pertinent to the field prior to 17 September 2008 and said that he was unable to identify in those publications any listing for acridines, acriflavine or proflavine for use in a therapeutic context. Both Professors Laven and Whittem agreed in cross-examination that many of the textbooks produced by Professor Huxley were commonly used textbooks in the field of veterinary medicine and mastitis control. The conclusion that Professor Huxley drew from the absence of a listing for acridines, acriflavine or proflavine for use in a therapeutic context in these textbooks is that they are not and were not, prior to 17 September 2008, widely used or known by those working in the field.

222    Associate Professor Bunt gave evidence to the following effect. In his experience, acridines are not and were not, prior to 17 September 2008, commonly used in the field and especially not internally as antiseptics. The field is the prevention of mastitis in cows and, in particular, internal teat seals. Acriflavine is not commonly found as an antiseptic agent in commercial veterinary antiseptic solutions and the use of antiseptic acridines was very uncommon in the field. It was widely accepted in the field prior to 17 September 2008 that acridines have very limited practical utility as antibacterial agents and that acridines were rarely used as antiseptics after the “mid-twentieth century”. Associate Professor Bunt said the following:

… I have formulated dozens of antimicrobial formulations. In the entire course of my career, I have never made, tried to make, considered making, or been asked to make any formulation containing an acridine, nor do I recall any reference to any formulation of an acridine antiseptic at any of the numerous conferences which I have attended, or in any conference abstracts I have seen. I do not and have not used acridines for any purpose in my laboratory. I am aware that acridines are used as dyes and stains.

223    Associate Professor Bunt said that if he had been asked to make a formulation described in the Opposed Application prior to 17 September 2008 and it had been suggested to him that he use an acridine as an antiseptic, he would have regarded acridines “as unsuitable for use in the formulations due, in part, to the irritancy issues” and that, in light of those issues, he would not have regarded acridines as physiologically acceptable, that is to say, tolerated and non-toxic at the concentration or dosage at which they would need to be used. He identified the irritancy issues and said that acriflavine was known to cause irritancy and, in some cases, extreme irritancy when used internally in various applications. Associate Professor Bunt said that, in his experience, irritancy is a particularly significant consideration when formulating a means to prevent mastitis in a dairy herd over the dry period.

224    Professor Laven’s qualifications are referred to earlier in these reasons. He has published over 150 peer-reviewed articles, over 25 of which related to mastitis, and over 200 non-peer reviewed articles, many of which have focused on mastitis. He has conducted extensive work in relation to teat seals. He said that he had never used acriflavine as a disinfectant in treating dairy cows or any other animal. He accepted that irritation was one factor against the use of acridines as antiseptics in the field of dairy cows.

225    Professor Wainwright said that antiseptics such as chlorhexidine, BZK, cetrimide, cetylpyridinium chloride and triclosan were in widespread use during the decades immediately prior to 2008, whereas the use of antiseptic acridines was less widespread. Under cross-examination, he agreed that persons in his field assumed that acridines were obsolete and he agreed that the title of his article, Wainwright M, Acridine – a neglected antimicrobial chromophore”, Journal of Antimicrobial Chemotherapy (2001) 47, 1–13, was accurate. He agreed that his object in publishing the various articles to which he was referred was to remind the scientific community “of these forgotten antiseptics”. Under cross-examination, he agreed that the potential use of acridines is limited to anti-malarial and trypanocidal work, neither of which has anything to do with the treatment or prevention of mastitis.

226    Professor Whittem said that acridines “became less frequently used as a result of the discovery of the penicillin and aminoglycoside classes of microbial compounds, which overtook acridines in popularity”. The respondent points to the fact that when first asked to identify the common general knowledge in the field before the priority date, Professor Whittem made no reference to acridines, although he did refer to the Meaney 1977 paper. Professor Whittem agreed the following was a correct statement as at 1991:

These dyes were of considerable importance as bacteriostatic antiseptics but, as with the other non-specific bacteriostats, their importance has waned.

227    This then is the evidence given by the experts. The respondent also addressed the publications referred to by the appellant’s experts.

228    Professor Wainwright referred to Albert’s textbook. He described it as the leading textbook dealing with the class of antimicrobial chromophores and the pre-eminent textbook on the class of acridine compounds to this day.

229    The respondent made the following points about Albert. The second edition of Albert was published in 1966 which is more than 40 years before the priority date. There has never been a third edition. There is no evidence that any person in Australia ever read Albert, and Associate Professor Bunt said in his affidavit that he had never heard of Albert prior to his involvement in the opposition proceedings. There is no evidence as to the availability of Albert in Australia and there is no evidence as to the extent to which, if at all, Albert continues to be used by any person in Australia. There is no evidence as to the extent to which the contents of Albert were generally accepted in Australia in 1966 and in 2008. Under cross-examination, Professor Wainwright said that he did not know to what extent anyone in Australia read Albert in the four decades between its publication and the priority date. The respondent’s case is that, in those circumstances, the appellant has not established that the contents of Albert were common general knowledge shortly before the priority date, even in the field of antimicrobial chemotherapy.

230    The respondent produced a further page from Albert and submitted that, in any event, there are clear disadvantages with acriflavine as indicated in the following passage:

Acriflavine has been widely used as a local antibacterial from 1917 onwards. From 1940 onwards clinicians began to realize that it was a much more damaging substance than proflavine, thanks largely to the work of Russell and Falconer (1940, 1941), mentioned above. Garrod (1940) ably marshalled the evidence, and recommended that proflavine should replace acriflavine. More recently the tendency is to replace these yellow-staining acridines by the non-staining types (see above).

Acriflavine has no advantages over aminacrine, and has the following disadvantages: (a) it is highly acid, (b) it is highly toxic to tissues even when neutralized, (c) it causes disfiguring stains. As relatively little acriflavine is used clinically, and that from traditional rather than from scientific motives, little space need be given it here.

An excellent review of the history of acriflavine as a local antiseptic has been published (Browning, 1943), and the experiences obtained with it in the First World War are on record (War Office, 1922).

Allergic idiosyncrasy to acriflavine has sometimes been recorded after repeated applications of the solution to wounds or ulcers (Young and Hawking, 1938; Sneddon, 1946). Such cases have usually acquired no sensitivity to another acridine, such as ethacridine (Young, 1939).

231    The respondent submitted that if the contents of Albert were common general knowledge shortly before the priority date, “it must follow that acriflavine was known and generally accepted to be wholly unsuitable for use in the invention claimed in the Application”. Under cross-examination, Professor Wainwright agreed that Albert was an authoritative text explaining 42 years before the date of the Opposed Application that acriflavine is damaging, it is highly toxic and it is relatively little used and that it was “potentially” saying that it would be a waste of space to say anything more about acriflavine. Professor Wainwright also agreed that acriflavine was being superseded as early as 1940.

232    Professor Wainwright referred to Patrick and Thomas as two leading textbooks used to teach undergraduate medicinal chemistry subjects. The reference to Patrick is a reference to Patrick G, An Introduction to Medical Chemistry (2nd ed, Oxford University Press, 2001). It contains the following statement:

Aminoacridine agents such as proflavine (Fig. 7.9) are topical antibacterial agents which were used particularly in the Second World War to treat surface wounds.

233    In the course of his evidence, Professor Wainwright agreed that there is no reference to the ongoing use of aminoacridine agents and nor is there any suggestion that they could be used, other than to treat surface wounds, or in veterinary science. There is no evidence that Patrick is available in Australia, or that the contents of it were generally known and accepted by those working in the field.

234    The reference to Thomas is a reference to Thomas G, Fundamentals of Medicinal Chemistry (John Wiley & Sons, 2000). As the respondent pointed out, the term “acridine” is not even used and the acridine class of compounds is not identified. Professor Wainwright agreed that the word “acridine” is not referred to on the pages he extracted other than in figure 7.13 where there is a depiction of the chemical structure of proflavine. This is the closest the entire book gets to a reference to acridines and none of the text of the book contains any information regarding the manner in which proflavine is being used, or is currently being used. There is no evidence that Thomas is available in Australia, and no evidence that the whole of the contents of this textbook was generally known and accepted by those working in the field.

235    Professor Wainwright (following Associate Professor Bunt’s reference) referred to an article by Russell AD in the Journal of Applied Microbiology Symposium Supplement 2002 entitled “Introduction of biocides into clinical practice and the impact on antibiotic-resistant bacteria”. The article contains the following statement:

In the early part of the twentieth century, other chlorine-releasing agents (CRAs), and acridine and other dyes were introduced, as were some quaternary ammonium compounds (QACs, although these were only used as biocides from the 1930s).

236    Table 3 in the publication indicates that acridines, including acriflavine and proflavine, were “now little used”. There is no evidence that the article is available in Australia. The respondent contends that there is no evidence that the whole of its contents was generally known and accepted by those working in the field.

237    Professor Wainwright said the following under cross-examination:

So, can I put it to you that none of these three text books, Albert, Patrick or Thomas, establish any continuing use of acridines around 2008?---That would be correct, yes.

Well, can I put it to you that even in your field of synthetic chemistry, very little reference was made to acridines and that reference was largely confined to comments on their historical use during World War II. Do you accept that?---In the two undergraduate text books that we just discussed, yes, I agree with that. In Albert’s book, of course, the whole thing is about acridines. But, as you say, that is a book from 1966.

Yes. So – well you refer to these books now as “undergraduate text books”, but these are the books that you have cited under the heading in your affidavit where you wish to make a point that antiseptic acridines are not merely historical. Can I put it to you, Professor Wainwright, that these very text books demonstrate quite how historical antiseptic acridines are. Do you accept that, Professor Wainwright?---I – I guess you – you could read it that way, yes.

238    Professor Wainwright also referred to various journal articles he had authored or previously cited. He agreed that none of them were concerned with veterinary science or, more particularly, mastitis. He agreed that a person reading his article titled “Acridine – a neglected antimicrobial chromophore” would reasonably conclude that as at 2002, acridines were, in fact, little used and generally neglected by people in his field.

239    In his first affidavit, Professor Wainwright discussed QACs and, in the course of that discussion, he referred to a chemistry reference text which he regularly consulted in the course of his work, namely, Kirk-Othmer’s Concise Encyclopaedia of Chemical Technology (4th ed, John Wiley & Sons, 2001). Professor Wainwright accepted that there is no reference in Kirk-Othmer’s textbook to acridines, acriflavine or euflavine in the chapter dealing with disinfectants and antiseptics. Under cross-examination he agreed that the absence of a reference was consistent with the fact that as far as Kirk-Othmer is concerned, antimicrobial chemotherapy acridines were forgotten and obsolete.

240    Professor Laven identified a small number of journal articles which made reference to acridines. The first was a paper published in The Australian Veterinary Journal in October 1946 entitled “Clinical Bovine Mastitis, Its Treatment and Control”. The respondent submitted that there is no evidence as to the extent to which any reference was ever made to that article in the intervening 70 years before the priority date and that the appellant has failed to establish that it formed any part of the common general knowledge.

241    As far as Dr Meaney’s papers (1977: “Effect of a Dry Period Teat Seal on Bovine Udder Infection”; 2001: “The Use of a Bismuth Based Teat Seal and the Bacteriocin Lacticin 3147 to Prevent Dry Period Mastitis in Dairy Cows”) are concerned, the respondent submits that neither of these papers establishes that the existence or use of acriflavine as an antiseptic was common general knowledge at the priority date. The first paper was published in 1977 and contains a reference in a footnote to acriflavine being part of the composition of a teat seal. Professor Huxley said that he read this article on a number of occasions in the course of writing his PhD thesis. He had no recollection “whatsoever” of acriflavine being mentioned in this article. Professor Laven could not tell from the paper whether the acriflavine had been used as an antiseptic, preservative or dye and he considered that acriflavine was not there for its antibacterial activity. Under cross-examination, Professor Wainwright agreed that the Meaney 1977 paper did not provide any support for a conclusion that acridines continued to be used as at 2008 in veterinary science.

242    The Meaney 2001 paper referred to the use of an internal sealer comprising bismuth subnitrate and acriflavine, but states that further work is required. The paper also contained the following statement:

A significant outcome of our trials was the in vivo evidence of the ability of lacticin 3147 to retain activity against Str. dysgalactiae in the teat and prevent the onset of clinical mastitis during the 8-day trial period. This trial provided convincing evidence that the bismuth-based teat seal and lacticin 3147 combination offered very effective protection against a significant challenge with an important mastitis-causing pathogen.

Lacticin is a bacteriocin which is not an acridine. The paper did not outline any further work in relation to the internal sealer comprising bismuth subnitrate and acriflavine.

243    Professor Whittem referred to four general veterinary textbooks and reference manuals that he consulted before the priority date. He said that he considered any antiseptic compounds included in general veterinary textbooks and reference manuals to be generally known and used prior to 17 September 2008.

244    The first work that Professor Whittem referred to is Greig J (ed), Hoare’s Veterinary Materia Medica & Therapeutics (5th ed, Baillière, Tindall and Cox, 1936). The fifth edition of this textbook was published in 1939 and, as the respondent pointed out, there is no evidence that a sixth edition was ever published. There is a short reference to acriflavine in the work. It is not described as an acridine. As the respondent also pointed out, there is no evidence as to the extent to which, if at all, any person in Australia was aware of the six line reference to acriflavine in a text published approximately 70 years before the priority date.

245    The second work is Jenkins, which I have referred to above. This text was published 17 years before the priority date. It contains a small number of paragraphs dealing with acridine derivatives, including acriflavine. It is stated that acridine derivatives, which are dyes, were of considerable importance as bacteriostatic antiseptics but, as with other non­specific bacteriostats, their importance has waned. They are said to possess little activity against Gram-negative organisms.

246    The third work is Kahn C (ed), The Merck Veterinary Manual (9th ed, Merck & Co., 2005). That is a publication of over 2,158 pages and, as the respondent pointed out, there is no evidence as to the extent to which any persons in the field read or generally accepted the information appearing on page 2,158. The relevant passage appears under the heading “Other Antibacterial Agents” and is as follows:

Acridine dyes (eg, acriflavine, proflavine, aminacrine) are more active against gram­positive bacteria. Their activity is enhanced in alkaline medium and antagonized by hypochlorites. Impregnated bandages and gauze and acriflavine jelly have been used extensively for treatment of burns.

Under cross-examination, Professor Whittem agreed that this passage was saying that acridine dyes were more active against Gram-positive bacteria than Gram-negative bacteria and that they have been used extensively for the treatment of burns. He agreed that the reference to acriflavine is brief. Professor Whittem agreed that none of the texts to which he referred state that acriflavine is commonly used as an antiseptic in veterinary medicine.

247    The fourth work is the MIMS IVS Annual for both Australia and New Zealand, 2008. Professor Whittem said that he regularly consulted these texts before 17 September 2008. He agreed that neither MIMS discloses that acriflavine could be used for the prevention of mastitis. MIMS Australia identifies various antiseptic sprays, wipes and teat dips to prevent bovine mastitis. They include Hibitane Teat Dip and Spray which contains chlorhexidine and controls mastitis-causing organisms on cows teats. It discloses Idedex Teat Dip and Spray which contains iodine and is described as “Post milking teat sanitiser with emollient”. It contains directions as to the application of the spray to the udder of the cow. I have already referred to the reference to Yellow Lotion which is stated to contain acriflavine. Professor Huxley said the term “proud flesh” is most commonly used in relation to horses as horses are most prone to the condition described and that, in his view, in light of the description, indications and directions for use, “this product has nothing to do with mastitis prevention or treatment in dairy cows”. In his oral evidence, Professor Whittem said that the Yellow Lotion product is not designed for treating mastitis.

248    In his second affidavit, Professor Whittem said that he disagreed with Professor Cook’s statement that the use of acridine antiseptics was largely historical. However, he was able to identify two products as being the subject of ongoing use. First, Yellow Lotion was targeted at horses and, in addition, no witness gave evidence that they had ever used Yellow Lotion before the priority date. The second, Septicide Cream, is a product registered to be used in Australia on dogs and horses and the listing in MIMS describes it as an “Insect repellent and antiseptic cream for use on the wounds of dogs and horses”. Professor Huxley said that Septicide Cream was utterly irrelevant for mastitis.

249    The respondent submits that the continuing existence of two products never used by any of the six experts in this proceeding which might be used to treat cuts and repel insects on dogs and horses, and which are described as containing acriflavine and proflavine respectively, falls a long way short of refuting the proposition that the use of acridines “was largely historical”. It certainly does not establish that it was common general knowledge that acridines had any characteristics which might render them suitable for use as antiseptics in teat seals.

250    My conclusions and reasons as to matters of common general knowledge shortly before the priority date with respect to acridines, their properties and their uses are as follows:

(1)    It was common general knowledge shortly before the priority date that acriflavine had an antiseptic property;

(2)    The characteristics of antiseptic acridines and, in particular, that some of them are ionised antiseptics and/or QACs were not common general knowledge shortly before the priority date; and

(3)    The use of acriflavine or, indeed, any antiseptic acridines in a teat seal was not common general knowledge shortly before the priority date.

251    With respect to acriflavine having an antiseptic property, the finding of the delegate in the substantive opposition proceeding is binding on the parties. In any event, the evidence before the Court supports the conclusion that it was common general knowledge shortly before the priority date that acriflavine had an antiseptic property. Although I consider Professor Cook’s evidence that acridines were largely of historical interest to be a fair summary of the position established by the evidence and Professor Wainwright’s assumption that, as far as his colleagues are concerned, acridines were largely forgotten and obsolete to be accurate, there is sufficient support for the finding in Professor Whittem’s evidence that he was aware of and had used certain antiseptics, including acriflavine before the priority date, based on MIMS Australia and the two products listed in MIMS Australia, including Yellow Lotion.

252    I turn to the characteristics of antiseptic acridines and, in particular, that some of them are ionised antiseptics and/or QACs.

253    Professor Cook said that acridine orange was not a QAC and he was not aware whether other acridines were QACs. Professor Huxley was not familiar with acridines or what they are used for and he gave evidence that, without consulting reference materials, he did not know whether acridines were ionised antiseptics or QACs. Associate Professor Bunt gave evidence that he did not know whether acridines were ionised antiseptics. Professor Laven did not give evidence that he was aware shortly before the priority date that acridines were ionised antiseptics or QACS. Professor Whittem gave evidence that he did not know whether acriflavine, which he had identified as an acridine of which he was aware of before the priority date, was a QAC. Professor Wainwright knew shortly before the priority date that some acridines are ionised antiseptics and/or QACs, but it is clear that his knowledge of acridines was exceptional and beyond that of the ordinarily skilled expert in antimicrobial compounds or antiseptics. I refer to my earlier discussion of his expertise (at [169]–[172]). I have identified various publications referred to by the parties in the course of summarising the respondent’s submissions as to common general knowledge. They do not support a conclusion on the balance of probabilities that the characteristics of some acridines as ionised antiseptics and/or QACs was a matter of common general knowledge shortly before the priority date.

254    I turn to the use of acriflavine or, indeed, any antiseptic acridine in a teat seal.

255    There is the finding of the delegate in the substantive opposition proceeding that the evidence did not establish that teat seal formulations containing acriflavine was part of common general knowledge. In any event, the evidence in this case does not establish that the use of acriflavine or, indeed, any antiseptic acridines in a teat seal was common general knowledge shortly before the priority date.

256    The appellant relied on the evidence of Professors Whittem and Laven. As I have said, Professor Whittem made a statutory declaration in the opposition filed by Pfizer, Inc to New Zealand Patent Application No 571347 on 13 December 2011 in which he outlined his opinion as to the state of common general knowledge of skilled workers in the field shortly before the priority date. He referred to patent disclosures of internal teat seal formulations and, in that context, he referred, without further comment, to the Meaney 1977 paper. In oral evidence, he said that there was a history of acriflavine being incorporated in a teat seal and not causing toxicity issues and referred to a study in evidence. Professor Laven agreed. This, it seems, is a reference to the Meaney 1977 paper and Professor Laven had earlier said in his oral evidence that Dr Meaney had “just used a product that was commercially available”. Professor Laven described how he became aware of both of Dr Meaney’s papers and he said that Dr Meaney was a world-renowned researcher in the field.

257    The appellant submits that Associate Professor Bunt and Professor Huxley were also aware of acriflavine being used in teat seals before the priority date.

258    Associate Professor Bunt referred to GB2,273,441 in his affidavit. In his oral evidence, he said that he was aware of that Patent Application before the priority date. That Patent Application relates to a composition for treating mastitis in dry cows comprising “an antibacterial and a seal comprising a gel base containing a heavy metal salt”. He recalled that there was a compound called acriflavine in it as a pigment. He did not know then that it was an antiseptic.

259    Professor Huxley recalls reading the Meaney 1977 paper on several occasions prior to the priority date, but had no recollection “whatsoever” of acriflavine being mentioned in this article.

260    In determining this issue, it is to be borne in mind that information or knowledge is common general knowledge only if it is accepted and assimilated into the knowledge of all, or the bulk, of those in the relevant field, and the fact that information appears in a publication read, even widely read by those in the field, does not of itself establish that the information was common general knowledge at the relevant date. Although the evidence advanced by the appellant establishes that some in the field knew of the use of acriflavine in a teat seal, it does not satisfy the requirements to which I have referred.

The Amendments are Allowable

261    The respondent accepted that, as a matter of scientific fact, antiseptic acridines fall within the definition of “antiseptic” and “antiseptic compound” in the Opposed Application. That is correct. If it is necessary in order to reach the conclusion that antiseptic acridines fall within the definition of antiseptic and antiseptic compound in the Opposed Application to consider the state of common general knowledge shortly before the priority date, then I reach the same conclusion because, as I have said, I find that it was common general knowledge shortly before the priority date that an antiseptic acridine, acriflavine, had an antiseptic property.

262    Leaving aside for analysis later in these reasons whether the Opposed Application indicates that antiseptic acridines are preferred antiseptics (or positively recommends them), that means the question is whether there is a real and reasonably clear disclosure in the body of the specification of the Opposed Application of antiseptic compounds other than acridines. The appellant submitted that, in the circumstances, an amendment of the nature sought can only be sustained where there is a disclosure that acridines are not to be used. There is no such disclosure and all of the experts agree that that is the case. On the other hand, the proposed amendments narrow the class of antiseptic compounds to which the claims apply and the authorities to which I have referred indicate that usually such an amendment is allowable in circumstances where the amended claims do not travel beyond the disclosure in the body of the specification. I refer, in particular, to Olin, Lockwood No 1, Emperor Sports and United States Gypsum.

263    I see no reason not to take that approach in this case. The first example given by the Court in AstraZeneca of the circumstances in which a narrowing of a claim or, the claiming of less than what is described in the body of the specification, may not result in a real and reasonably clear disclosure of what is claimed after the amendment does not apply in this case because, in my opinion, there is a real and reasonably clear disclosure in the body of the specification of the antiseptic compounds claimed after the amendment.

264    The other main argument advanced by the appellant is that acriflavine and other antiseptic acridines have the preferred properties, have poor absorption characteristics and are ionised antiseptics and are QACs. There is no basis upon which to exclude acridines generally or acriflavine specifically. In its closing submissions, the appellant put the matter in the following way. Acriflavine is within the express statements in the Opposed Application of a suitable, indeed preferred, antiseptic because ionised antiseptics and, in particular, QACs are identified as suitable antiseptics and antiseptic acridines (including acriflavine) are ionised antiseptics and some acridine antiseptics (including acriflavine) are also QACs. The effect of the amendments is to redefine the invention. Antiseptic acridines are excluded, but all other antiseptics, whether or not they are ionised antiseptics or QACs or otherwise exhibit the preferred characteristics, remain. The disclosure in the body of the specification as to the use of acridines is fundamentally inconsistent with the amended claims which exclude acridines. This is the second example given by the Court in AstraZeneca. It is engaged, or potentially engaged, where the body of the specification identifies as preferred or positively recommends the use of compounds subsequently excluded by amendment. The appellant’s argument fails because that proposition is not established.

265    The Opposed Application refers to four antiseptics by name: chlorhexidine, cetrimide, BZK and povidone-iodine. The Opposed Application overwhelmingly indicates that the preferred antiseptic in the invention is chlorhexidine. That was not disputed. As I have said, acridines, antiseptic acridines or acriflavine are not mentioned by name in the Opposed Application.

266    The appellant submitted that antiseptic acridines are preferred antiseptics because they are mixable with a barrier material and have one of the six properties referred to in the first passage. Indeed, it relies on evidence given by Professor Whittem that antiseptic acridines have, or, after testing, are likely to be shown to have most, if not all, of the six properties. This gave antiseptic acridines a higher preferred status than if they had met only one of the preferred properties. Professor Wainwright agreed with this evidence. The difficulty for the appellant in terms of this last aspect of Professor Whittem’s evidence is that the evidence is based on a proposition about the content of common general knowledge — the effective use of acriflavine in targeting the pathogen linked to mastitis — which I have rejected.

267    The respondent’s experts gave evidence of potential problems with antiseptic acridines in relation to toxicity, irritancy and lack of broad spectrum activity. The appellant is correct to say that aspects of that evidence is based on knowledge gained after the priority date and not shown to be common general knowledge shortly before the priority date.

268    There are two unusual features of the class consisting of antiseptics which have one of the six properties referred to in the first passage. First, the class consisted of a large number of “preferred” antiseptics. Secondly, and more significantly, as I understood the evidence, the class would, or is likely to, include antiseptics which do not have desirable properties and are unsuitable for other reasons. Those two features of the class mean, even if the appellant was otherwise to establish disclosure of antiseptic acridines by reference to the six properties identified in the first passage, that would not amount to a positive recommendation to use them sufficient to engage the notion of fundamental inconsistency referred to in AstraZeneca.

269    In this context, it will be recalled that the experts were asked to identify the antiseptic compounds or types of antiseptic compounds the Opposed Application disclosed as being preferred for use in the claimed composition and that Professor Huxley and Associate Professor Bunt favoured Interpretation 1, Professors Wainwright and Whittem favoured Interpretation 2, and Professors Laven and Cook expressed a slight preference for Interpretation 1, but stated that both interpretations were reasonable (see [129]–[138]). Leaving aside the issue of the extent to which “ionised antiseptics” and “QACs” are preferred antiseptics by reason of the third passage on page 13 of the Opposed Application, of the two interpretations I prefer Interpretation 1 for the reasons given by Professor Huxley and Associate Professor Bunt, and because the question of preferred antiseptics is more directly addressed in the third passage and because of the large number of compounds produced by Interpretation 2. As I have said, even if antiseptics which are mixable with the barrier material and have one or more of the six properties in the first passage are recognised as having some form of preference, they are so far down the cascading levels of preferred antiseptics on this assumption, that the principle or approach in AstraZeneca is not engaged.

270    The focus of the appellant’s argument was the third passage in the Opposed Application. The appellant submitted that, although it does not name acridines, antiseptic acridines or acriflavine, nevertheless, they are within its terms. As a matter of scientific fact, there are some acridines which are ionised antiseptics and there are ionised antiseptics which are not acridines. As a matter of scientific fact, some ionised acridines are QACs and some ionised acridines are not QACs. According to Professor Wainwright, there are probably thousands of QACs which are not acridines.

271    The first issue is one of construction: what does the third passage mean? The context for the passage is that chlorhexidine is overwhelmingly the preferred antiseptic. A statement is made that it can provide the desired characteristics to the formulation and that it has the further advantage which, on the expert evidence in this case, I find to be considerable, of proving acceptable for veterinary use and having been used in dairy practices for some time. Chlorhexidine is well known and well tested and is believed not to be absorbed through the teat wall into the body of the animal.

272    The relevant context also includes the fact that the common general knowledge shortly before the priority date was that the other three named compounds, cetrimide, BZK and povidone-iodine were well-known and common antiseptics. The third passage includes the statement that antiseptics with poor absorption characteristics are preferred and these (that is, antiseptics with poor absorption characteristics) may include, by way of example, ionised antiseptics. This is an indication to the reader that ionised antiseptics may have the desired characteristic of being poorly absorbed by the animal’s body. As a matter of scientific fact, some acridines are ionised antiseptics and they form a subclass of ionised antiseptics.

273    The third passage goes on to state, by way of example, that QACs may be suitable, including but not limited to cetrimide, BZK and povidone-iodine, and as to the latter, there is the additional statement that the compound is currently used in the dairy industry. The experts were asked to address what they understood by the use of the term “QAC”. The opinion of the respondent’s experts is summarised above (at [141]) as is Professor Wainwright’s opposing view (at [142]). The difference also reflects in part, at least, a difference between the parties as to the relevance of common general knowledge to the construction and meaning of the third passage. The respondent submits that the terms “ionised antiseptic” and “QAC” are to be interpreted in light of common general knowledge, whereas the appellant (at least on one of its arguments) submits that a compound falls within those terms if it does as a matter of scientific fact.

274    I have already set out the position as a matter of scientific fact and I have set out my findings as to the common general knowledge at the priority date. If the matter is assessed by reference to the common general knowledge at the priority date, the skilled addressee would not be aware of the characteristics of acridines such that he or she could draw any conclusion as to whether they are ionised antiseptics and/or QACs. Further, that lack of knowledge supports the opinion of the respondent’s experts that the term “quaternary ammonium compounds”, as used in the third passage, is used as a noun and would not normally be considered to contain acridines (see [141] above).

275    Even if I am wrong about the content of common general knowledge or about its relevance to the meaning of the termsionised antiseptics” and “QAC, nevertheless, in my opinion, there is no positive recommendation to use acridines such that there is a fundamental inconsistency between the body of the specification and the amended claims. That is because the skilled addressee would know that there were over a thousand ionised antiseptics and QACs which are not acridines and over a thousand acridines which are not ionised antiseptics and QACs. That, to my mind, means that this case falls well short of the type of positive recommendation before the Court in AstraZeneca. That position is only made stronger if, as the respondent suggested, the skilled addressee is also armed with knowledge of the following: (1) acridines are rarely used and historical (see at [251] above); (2) it is not suggested in any of the relevant text books that acridines should be considered in veterinary medicine (see at [260] above); (3) there are numerous more commonly used safe and effective antiseptics than acridines; and (4) Albert referred to acriflavine as highly acidic and toxic and little used.

Conclusion

276    In my opinion, the amendments are allowable and the appeal must be dismissed. I will hear the parties as to the appropriate orders.

I certify that the preceding two hundred and seventy-six (276) numbered paragraphs are a true copy of the Reasons for Judgment of the Honourable Justice Besanko.

Associate:    

Dated:    25 November 2021