[The IPKat] Australian court (over)simplifies approach to assessing "whole of contents" novelty

[Claire Gregg]

Australian court (over)simplifies approach to assessing "whole of contents" novelty

 Dr Claire Gregg Monday, November 24, 2025 - Australia, Claire Gregg, OzKat, patents, whole of contents novelty

While so-called "whole of contents" (WOC) novelty has its origins in the European Patent Convention (EPC), like many other aspects of patent law, Australia has adopted and developed its own unique approach to its assessment, which continues to evolve. A recent decision by the Federal Court in Abbey Laboratories Pty Ltd v Virbac (Australia) Pty Ltd (No 3) [2025] FCA 1179 has rejected the previous approach by the courts to assessing the validity of a "notional claim" set derived from a WOC novelty citation. But is the new approach an oversimplification?

WOC novelty

In Australia, the Patents Act 1990 (Cth) (Act) specifies that the prior art base for assessing novelty includes information contained in a published specification filed in respect of a complete (non-provisional) application where:

1.                  if the information is, or were to be, the subject of a claim of the specification, the claim has, or would have, a priority date earlier than that of the claim under consideration; and

2.                  the specification was published on or after the priority date of the claim under consideration; and

3.                  the information was contained in the specification on its filing date.

Essentially, the Australian approach to assessing WOC novelty differs from that in the UK and Europe to the extent that the prior art includes PCT applications that designate Australia, regardless of whether national phase is ever entered in Australia. In contrast, a PCT application is only considered part of the prior art base (or "state of the art") for WOC novelty in the UK and Europe if it has entered the national or regional phase, respectively.

The broader Australian approach is arguably unjustified in view of the fact that WOC is intended to prevent double patenting (which cannot occur if a PCT application never enters the national phase in Australia), but that is an argument for another day.

Double Patenting Kat

The "notional claim" approach to WOC novelty

Previously, the Federal Court found that assessing WOC novelty under Australian law involves asking: (i) whether there is any information in the earlier application that anticipates the claim in question; and (ii) whether that information is the subject of a claim, or could be the subject of a valid notional claim having regard to the relevant disclosure requirements for valid priority claiming (EI du Pont de Nemours Co v ICI Chemicals & Polymers Ltd [2005] FCA 892).

The du Pont decision resulted in a practice whereby challengers to the validity of a patent routinely produced a notional set of claims when raising WOC novelty as a ground of revocation (see, e.g., Danisco A/S v Novozymes A/S (No 2) [2011] FCA 282; DSI Australia (Holdings) Pty Ltd v Garford Pty Ltd [2013] FCA 132; Hanwha Solutions Corp v REC Solar Pte Ltd [2023] FCA 1017).

(Over)simplified assessment of WOC novelty

In Abbey, Jackman J found there were "compelling reasons" to depart from du Pont and that the assessment of WOC novelty does not necessitate the drafting of a notional claim set or the assessment of the hypothetical validity of those claims to determine whether a WOC citation is anticipatory. In other words, the Act allows for assessing information as if it were in a claim without requiring the actual drafting of a notional claim, thereby avoiding the "tangential and burdensome enquiry" du Pont placed on the parties and courts.

Jackman J also acknowledged that the legislative intent behind the WOC provisions was to simplify the assessment of novelty relative to the previous "prior claiming" approach, and that drafting and assessing the validity of notional claims did not achieve this intention. His Honour concluded all that is required is "a comparison between the information in a specification as published, and the priority document".

However, this approach presupposes "whole of contents" is a novelty assessment (perhaps misguided by its inclusion in the definition of the prior art base for novelty in the Act), whereas it is in fact an assessment of the potential for double patenting, which arguably cannot occur without assessing whether the relevant patent application could give rise to a valid claim to the same invention.

A bigger problem remains

The decision of a single judge of the Federal Court is not binding on other single judges in Australia, so it remains to be seen whether Jackman J's views will prevail. His Honour took this fact into account in expressing his view that the notion of "judicial comity" runs the risk of "giv[ing] priority to questions of courtesy and politeness to each other over their duty to apply the law as properly understood".

Regarding WOC novelty, while this decision could serve to reduce the burden on parties during proceedings, it not only does not address the fundamental objectives of the WOC novelty provisions, it also does not address the problem for patentees that the assessment of WOC novelty in Australia includes all PCT applications designating Australia, which may be an unfamiliar concept to UK and European attorneys.

 

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