In brief

In Perfect Day, Inc. v Commissioner of Patents [2025] FCA 270, the Federal Court upheld a decision by the Commissioner of Patents which found that the claims of a patent application to a milk substitute product lacked support and that the specification did not provide sufficient disclosure. This decision follows the Federal Court’s approach to assessing the validity of post-Raising the Bar patents and serves as a reminder of the strict requirements for sufficiency of disclosure and support.

Background

Perfect Day, Inc. (Perfect Day) is a biotechnology company that specialises in producing animal-free dairy proteins using genetically modified microorganisms (like fungi) to produce proteins identical to those found in cow's milk.

Perfect Day filed the application in August 2015 claiming priority from an United States application filed on 21 August 2014. Therefore, the amendments to the Patents Act 1990 (Cth) (Patents Act) as made by the Intellectual Property Laws Amendment (Raising the Bar) Act 2012 (Cth) apply. The Application claimed certain compositions for a milk substitute product (the Application).

Opposition proceedings in the Australian Patent Office

In 2019, Fonterra Co-operative Group Ltd (Fonterra) opposed the Application proceeding to grant (the Opposition). A Delegate of the Commissioner of Patents handed down a decision in the opposition in August 2022.

The main issue in the Opposition was that the specification, including the title, centred on compositions containing casein proteins. However, the claims were restricted to food compositions consisting solely of α-lactalbumin (ALA) and β-lactoglobulin (BLG), but explicitly excluding any other milk proteins, and having one or more characteristics of a dairy food product, including taste, aroma, appearance, handling, mouthfeel, density, structure, texture, elasticity, springiness, coagulation, binding, leavening, aeration, foaming, creaminess, and emulsification.

Fonterra contended, and the Delegate agreed, that the complete specification did not disclose how to produce a dairy substitute food product with the specified functional characteristics without casein. As the claims did not define the invention in terms of a principle of general application, the Delegate held that none of the claims were enabled across the full scope of the invention claimed, thereby failing to meet the support requirement under section 40(3) of the Patents Act.

In relation to the sufficiency of disclosure requirement, the Delegate considered that the specification provided no guidance, or even a suggestion, that ALA and/or BLG could be used as a replacement for casein and would provide the structure, texture, mouthfeel and aggregation properties traditionally attributed to casein. The Delegate found that the lack of guidance, the uncertainty in the research and the associated trial and error that would inherently be required to work the invention claimed “based on a specification that essentially describes a completely different invention” would constitute an undue burden. The Delegate held that the specification failed to meet the sufficiency of disclosure requirement under section 40(2)(a) of the Patents Act.

Perfect Day appealed the Delegate's decision.

Federal Court Appeal

An appeal to the Federal Court from an opposition decision is a hearing de novo. Fonterra initially filed a notice of contention, but then withdrew from the proceedings. The Commissioner of Patents (the Commissioner), therefore, become the respondent in the Appeal in the interests of the public.

In the course of the proceedings, Perfect Day sought to amend its patent claims twice to focus on a food composition suitable as a dairy substitute, comprising two specific recombinant milk proteins, excluding casein. The appeal proceedings proceeded on the basis of the amended claims.

Construction

The parties disagreed on the interpretation of claim 1, specifically the meaning of the phrase “one or more” as it pertained to the list of dairy food product characteristics in claim 1.

Perfect Day argued that claim 1 is to be construed as requiring only one characteristic and that claim 1 should be viewed as 16 distinct claims, each describing a food composition containing ALA and BLG, without any other milk proteins, and featuring one of the specified characteristics. In contrast the Commissioner considered that a proper reading of claim 1 is that “one or more” means one, more than one or all of the listed characteristics. Justice Rofe preferred the Commissioner’s broader interpretation, which in turn had ramifications for Perfect Day’s arguments concerning sufficiency and support.

Lack of support

Section 40(3) of the Patents Act requires that the claim or claims must be “supported by matter disclosed in the specification”. On the plain wording of claim 1, Rofe J considered that in order to be valid, claim 1 at its broadest (i.e. the combination of all the listed characteristics) must be supported by the disclosure in the specification. When properly characterised, the invention claimed is a food composition that comprises ALA and BLG proteins as the only milk proteins and does not include casein or any other milk proteins. Rofe J found that the invention claimed was distinct from the one described in the specification, which, when viewed as a whole, describes a food composition comprising casein and possibly other milk proteins, as well as the methods for its production.

Perfect Day relied upon the consistory clause (and corresponding claim) as being sufficient disclosure and support for claim 1. Perfect Day also argued that the invention was narrowly focused, emphasising that its core innovation (or technical contribution) lay not in the list of characteristics in claim 1 themselves, but in creating a dairy substitute composition that mimics the desired traits or properties of the dairy product being replaced—whether it be milk, cheese, yogurt, or similar—using exclusively ALA and BLG without incorporating any other milk proteins. Perfect Day’s expert, Professor Tong stated in his affidavit that he would be able to make a formulation within that fell within the scope of claim 1.

Her Honour rejected Perfect Day’s submissions. Notably, in respect of synthetic milk, the specification expressly discloses that micelles of casein are very important for the optimum behaviour of milk and that if sufficient casein is not present then micelles will not form or if there is micelle formation but the casein content is poor, this can give rise to the bad mouth feel of synthetic milk products. Her Honour considered that in order to make the substitute dairy composition, the person skilled in the relevant art would have to make multiple formulations in multiple different ways and then test them to assess their characteristics, adjusting the ingredients and/or processing condition variables depending on the test results. Professor Tong suggested micelles could form in milk without casein, but conceded that he not know whether rALA and rBLG would do that and would have to carry out research to determine whether that was the case. The Application did not tell him how to do that and he would not have otherwise known how to do that. Professor Tong also conceded that he could not make a product that resembled a traditional enzymatic curd in its appearance, or structure on the basis of the disclosures in the specification. Rofe J therefore held that claim 1 lacked support.

Insufficient disclosure

Section 40(2)(a) of the Patents Act provides that a complete specification must disclose the invention in a manner which is clear enough and complete enough for the invention to be performed by a person skilled in the art. The enquiry is whether, given what is contained in the specification, the person skilled in the art can readily perform the invention without undue burden or experimentation beyond the ordinary steps of trial and error, or the need for further invention.

Following from Rofe J’s finding of lack of support, her Honour also held that claim 1 lacked sufficiency in that the specification did not disclose the invention claimed in claim 1 in a manner which is clear enough and complete enough for the invention to be performed by a person skilled in the relevant art. Her Honour found that the specification provided no guidance to the person skilled in the relevant art seeking to perform the invention by making a dairy substitute composition with two or more of the listed characteristics. In order to make a dairy substitute composition of claim 1, the person skilled in the relevant art must embark on a prolonged research program, enquiry or experimentation in order to implement the invention. It was not plausible that the invention claimed in claim 1 could be worked across the full scope of the claim (a composition with two, three or all of the listed characteristics) without undue burden.

Key lessons

This decision serves as a reminder of the relative strictness of the sufficiency and support requirements for post-Raising the Bar patents.

Claim amendments during prosecution may be aimed at avoiding prior art by exclusion of features. However, the exclusion may change the nature of the invention claimed. Such claims may be invalid for insufficiently disclosure and for lack of support if they are inconsistent with the teaching in the specification.