Patents: The Evolving Law Of Support And Sufficiency

For more than a decade, and for at least another decade to come, Australia's patent law has openly applied a double-standard with respect to written description requirements, namely the former sufficiency and fair basis tests, vs the current sufficiency and support tests.

The "old law", under the original Patents Act 1990 (Cth) (Patents Act) applies to patents for which examination was requested prior to 15 April 2013 when the "new law" commenced under the Intellectual Property Laws Amendment (Raising the Bar) Act 2012 (Cth) (RTB Act).

The old (pre-RTB) law subjected patents to sufficiency and fair basis tests that were not onerous for patentees – particularly those familiar with prosecution in jurisdictions such as the USA, UK, and Europe. Among the most significant changes in the new (post-RTB) law under the RTB Act were heightened requirements for sufficiency and the introduction of a more robust "support" requirement to replace the former fair basis test.

The relatively lenient and patentee-friendly nature of Australia's pre-RTB tests for sufficiency and fair basis meant that these grounds rarely posed significant obstacles during prosecution or litigation concerning the validity of pre-RTB patents.

In contrast, post-RTB support and sufficiency requirements are far more stringent, frequently giving rise to objections and amendments, and playing a central role in both pre-grant oppositions and post-grant litigation.

While every new Australian patent application is now subject to the more demanding post-RTB standards – including divisionals from pre-RTB families – pre-RTB law will continue to apply to patents for which examination was requested before 15 April 2013, with some potentially remaining in force until 2038 (if examination was requested in 2013 and a maximum 5-year pharmaceutical patent term extension is obtained).

As a result, with a substantial body of post-RTB case law now developed and many years of pre-RTB litigation still ahead, it is timely to reflect on both sets of requirements and their differences.

Pre-RTB law: "describe the invention fully" and "fair basis"

Section 40(2)(a) of the old law required that the specification "describe the invention fully", while s 40(3) required that the claims be "fairly based" on that description.

In Kimberly-Clark Australia Pty v Arico Trading International Pty Ltd [2001] HCA 8 and Lockwood v Doric (No 1) [2004] HCA 58, the High Court of Australia confirmed that these grounds address form, not substance, and are independent of novelty, inventive step and utility.

The "full description" test was generous: it sufficed that the skilled person could make one embodiment within each claim without invention or prolonged study. Enablement across the whole claim breadth was unnecessary. Under the pre-RTB sufficiency test, disclosure of a single embodiment could support very broad claim language.

The fair basis test was also patentee-friendly. In essence, it asked whether the claims were textually consistent with what the specification "describes as the invention", a standard often met by a suitably drafted consistory clause, provided it was consistent with the balance of the specification. Although the courts spoke of a need for a "real and reasonably clear disclosure" and whether claims "travel beyond the subject-matter of the invention described", the exercise was largely a comparison of words, not technical substance.

Post-RTB law: sufficiency of disclosure and support

The RTB Act replaced the full description requirement with a true "sufficiency" test: the specification must "disclose the invention in a manner which is clear enough and complete enough for the invention to be performed" by the skilled addressee across "the whole width of the claims" (s 40(2)(a)).

The old "fair basis" limb became a European-style "support" requirement: each claim must be "supported by" the matter disclosed and must not be broader than is justified by the patentee's technical contribution (s 40(3)).

The Explanatory Memorandum to the Intellectual Property Laws Amendment (Raising the Bar) Bill 2011 (Cth) (which became the RTB Act) confirmed that these amendments were intended to align Australian law with the corresponding UK and European standards (i.e., Patents Act 1977 (UK) ss 14(3) and 14(5) and European Patent Convention Articles 83 and 84).

We previously discussed the post-RTB requirements for disclosure and support in Australian patent specifications here.

The first Patent Office decision post-RTB

The Australian Patent Office's landmark decision in CSR Building Products Limited v United States Gypsum Company [2015] APO 72 articulated the core post-RTB tests.

• Sufficiency: "Can the skilled person readily perform the invention over the whole area claimed without undue burden and without needing inventive skill?". The decision-maker must (i) construe the claims; (ii) construe the description; and (iii) decide whether the disclosure enables all embodiments within the claims.
  
  A "reasonable amount of trial and error" is permitted, but there must be "adequate information leading necessarily and directly towards success". Where a claim employs a "principle of general application", the invention must "work with anything which falls within the general term".

• Support: The claim scope must correspond to the "technical contribution to the art". After construing the claims and the description, the decision-maker asks whether each claim is truly borne out by that contribution. The Delegate drew heavily on UK authority distinguishing an "inventive concept" from the "technical contribution".

The plausibility gloss on sufficiency of disclosure (enablement)

A few years after the CSR decision issued, the threshold of sufficiency was clarified in another Patent Office decision, Evolva SA [2017] APO 57, in which the Delegate adopted a plausibility test: based on the disclosure of the specification, it must be plausible that the invention can be worked across the full scope of the claims. A detailed analysis of the Evolva decision can be found in our previous article here.

Building on the CSR decision, and with reference to earlier UK authorities (e.g. Human Genome Sciences Inc v Eli Lilly & Co [2011] UKSC 51) and European jurisprudence, the Delegate resolved the question of what constitutes a clear enough and complete enough disclosure and advocated the following test (at [45]):

Does the specification provide an enabling disclosure of all the things that fall within the scope of the claims, and in particular:

1. Is it plausible that the invention can be worked across the full scope of the claims?
2. Can the invention be performed across the full scope of the claim without undue burden?

Adopting the UK Supreme Court's approach in Human Genome Sciences Inc v Eli Lilly & Co [2011] UKSC 51, the Delegate held that plausibility is a "low threshold" but nevertheless must exceed "mere speculation or assertion".

The Patent Office's decision in BASF Corporation [2019] APO 34 revisited these standards in light of the UK Supreme Court's decision in Warner-Lambert Company LLC v Generics (UK) Ltd [2018] UKSC 56, acknowledging that earlier UK guidance may have set the bar too low. A detailed analysis of the UK Warner-Lambert decision can be found in our previous article here.

The Patent Office's decision in Gary B Cox v MacroGenics, Inc. [2019] APO 13 reiterated that plausibility is "a threshold nonetheless".

The Federal Court has since endorsed this approach in Cytec Industries Inc. v Nalco Company [2021] FCA 970 and TCT Group Pty Ltd v Polaris IP Pty Ltd [2022] FCA 1493.

Sufficiency at the filing date

Both Evolva and Warner-Lambert confirmed that sufficiency (and thus plausibility) must be satisfied on the filing (or priority) date: post-filed data cannot cure a deficiency in enabling disclosure.

The first Federal Court decision contrasting the pre-RTB and post-RTB regimes

The decision of the Federal Court of Australia (Burley J) in Merck Sharp & Dohme Corporation v Wyeth LLC (No 3) [2020] FCA 1477 starkly illustrates the divergence between the pre-RTB and post-RTB written description requirements.

The parent patent, examined pre-RTB, survived a fair basis attack because the claim language mirrored the description. Its divisional counterpart, examined under the post-RTB standards, was held invalid on lack of support grounds: while the inclusive claim language (using "comprising") covered compositions containing 13 specified Streptococcus pneumoniae serotypes plus any others, the technical contribution disclosed in the body of the specification was limited to the 13-valent composition.

Our analysis of Merck is available in our previous article here.

Construction matters – the reach of "comprising"

Following his decision in Merck, Burley J adopted a similarly broad construction of the term "comprising" in Cytec Industries Inc. v Nalco Company [2021] FCA 970, and consequently found the patent claims invalid for insufficiency and lack of support under the post-RTB provisions.

Conversely, in Boehringer Ingelheim Animal Health USA Inc v Zoetis Services LLC [2023] FCA 1119, Rofe J adopted a narrower construction, holding that "comprising" did not extend to unrecited antigens, with the consequence that support and sufficiency were satisfied.

These caseshighlight that the construction of even the most commonly used terms in a patent is dependent on how the invention is described in the specification, and that this can ultimately impact the assessment of support and sufficiency post-RTB.

Claim construction is becoming ever more critical.

Added matter and "intermediate generalisation"

In 2020, the Federal Court of Australia considered the allowability of amendments to patent specifications under "added matter" provisions essentially mirroring the post-RTB sufficiency and support requirements.

In CSIRO v BASF Plant Science GmbH [2020] FCA 328, the Federal Court (Beach J) held that s 102(1) of the Patents Act (as amended by the RTB Act) imposes a "strict" prohibition on amendments introducing matter not "clearly and unambiguously" disclosed in the application as filed.

Drawing on Bonzel v Intervention Ltd (No 3) [1991] RPC 553, Richardson-Vicks Inc's Patent [1995] RPC 568 and European Central Bank v Document Security Systems Inc [2007] EWHC 600, Beach J adopted UK and EPO concepts of "added matter" and "intermediate generalisation": a patentee cannot lift isolated features from a specific embodiment and redeploy them in broader claims unless the generalisation itself is unmistakeably disclosed in the specification as filed.

In other words, the concept of "intermediate generalisation" stipulates that an amendment will not be not allowable, because a claim will not be supported, if it takes a feature which is only disclosed in a particular context and seeks to introduce it into a claim deprived of that context.

A fuller treatment of CSIRO is available here.

The "relevant range" (sufficiency and support)

The Full Court of the Federal Court of Australia in Jusand Nominees Pty Ltd v Rattlejack Innovations Pty Ltd [2023] FCAFC 178 applied the UK Supreme Court's reasoning in Regeneron Pharmaceuticals Inc v Kymab Ltd [2020] UKSC 27 and the reasoning of Birss J in Illumina Cambridge Limited v Latvia MGI Tech SIA [2021] EWHC 57 (Pat) to hold that a claim must be enabled across the whole of any technically "relevant range".

Because the patents failed to teach how to construct the claimed mining safety system from materials other than steel, the skilled person would face undue burden in seeking to work the invention across the full scope of the claims, which therefore lacked both sufficiency and support.

Our commentary on Jusand can be found here.

Sufficiency and priority

The Full Court of the Federal Court of Australia in Glass Hardware Australia Pty Ltd v TCT Group Pty Ltd [2024] FCAFC 95 confirmed that the statutory test for claiming priority (s 43) mirrors internal sufficiency (s 40(2)(a)).

The divisional patent in that case could not claim its parent's date because the parent did not "clearly disclose" the broader "striking surface" language. The same deficit rendered the patent itself insufficient. The decision echoes the Patent Office's reasoning in Fisher v ToolGen Inc [2018] APO 65.

Post-grant amendments

The decision of the Federal Court (Rofe J) in Miele & Cie KG v Bruckbauer [2025] FCA 537 demonstrates the peril of introducing post-grant amendments unsupported (assessed against the post-RTB standard in s 40(3) of the Patents Act) by the priority document. A one-fan hob configuration, first disclosed only in a 2015 amendment, could not rely on the original PCT filing and fell to intervening art.

Similarly, in The NOCO Company v Brown and Watson International Pty Ltd [2025] FCA 887, Moshinsky J denied priority where broadened divisional claims (power switches, sensor numbers, automatic start) were not disclosed in a manner "clear enough and complete enough" in the 2014 PCT application. Losing priority doomed the claims for lack of novelty.

Consistory clauses and "materially different" claims

In the case of Calix Limited v Grenof Pty Ltd [2023] FCA 378; 171 IPR 582, the specification of the patent in suit disclosed a method in which the maximum temperature the reaction mixture is permitted to reach is boiling point. However, Nicholas J decided that this did not support a claim to a method in which the maximum temperature of the reaction mixture is restricted to "near the boiling point".

In his Honour's view, the invention as defined by claim 1 was materially different from the invention disclosed in the body of the specification, with the consequence that claim 1 was found not to be supported by matter disclosed in the specification.

A detailed analysis of the Calix decision can be found in our previous article here.

Consistory clauses alone do not satisfy enablement requirements

In Perfect Day, Inc. v Commissioner of Patents [2025] FCA 270, Rofe J found the relevant claims invalid for insufficiency and lack of support under the post-RTB provisions. Notably, Rofe J found that support could not be provided by a consistory clause in circumstances where it was inconsistent with the rest of the patent specification.

European signals – Decision T 0878/23

Decision T 0878/23 on EP 3317395 B1 warns that mutually incompatible claim dependencies can render a patent insufficient where the skilled person cannot practice the invention across the entire claimed field. Australian tribunals, already alive to UK/EPO developments, are likely to take note.

Practical take-aways for patent drafters and litigators

A discussion of how the laws of disclosure and support affect drafting patent specifications can be found in our previous article here.

Key recommendations include:

• Establish the technical contribution early and draft claims commensurate with it.
• Provide data or logic rendering the invention plausible at filing; avoid relying on post-filed evidence.
• Disclose a principle of general application, or enough examples, so that the skilled person can work the invention across its full scope of the claims without undue burden.
• Include guidance enabling the identification and routine testing of alternatives that fall within broad terms.
• Avoid incorporating into broad claims features disclosed only in the context of narrow embodiments, unless the claimed combination is clearly and unambiguously disclosed; guard against "intermediate generalisations".
• Before filing divisionals or post-grant amendments, confirm that every broadened element is enabled in, and supported by, the priority document; otherwise the claim will lose its priority date and be exposed to novelty and obviousness attacks.
• Draft with claim construction in mind: under Australian law, commonplace terms such as "comprising" can be construed broadly or narrowly depending on context.
• Remember that consistory clauses alone do not confer support. The whole specification must march in step with the claims.

How we can help

Spruson & Ferguson has a large team of highly qualified and experienced patent attorneys and lawyers working collaboratively with clients of all sizes, globally. Our tailored services ensure we are well placed to assist and advise on patent drafting, prosecution and litigation across all science and technology fields.

If you would like assistance, please don't hesitate to reach out to our authors or your Spruson & Ferguson contact.

The content of this article is intended to provide a general guide to the subject matter. Specialist advice should be sought about your specific circumstances.