Safety First! Sufficiency in Australian patent law: Jusand v Rattlejack

Key takeaways:

• This is the first appellate decision in Australia concerned with the new test for sufficiency in section 40(2)(a) of the Patents Act.  
• If a product claim might import a relevant range of options, one approach is to identify the “essence or core” of the invention and then determine whether the range is relevant.
• If the range is relevant the specification must enable the skilled addressee to perform the invention across the entire breadth of the claim (including the range).

On 13 November 2023 the Full Court of the Federal Court of Australia delivered Australia’s first appellate judgment concerning the post-Raising the Bar amendments¹ to the support and sufficiency requirements in section 40 of the Patents Act 1990 (Cth). The lead judgment was given by Perram J, with whom Nicholas and McElwaine JJ agreed. The Full Court’s decision in Jusand Nominees Pty Ltd v Rattlejack Innovations Pty Ltd² (Rattlejack) considers these issues in detail.

Patent practitioners will know that the old “fair basis” test was replaced with the current “support” requirement and the old sufficiency test was expanded to require a complete specification to “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”. Most of the decision in Rattlejack focuses on this sufficiency aspect. Indeed, as the Court noted (as Burley J observed in one of only two other decided cases on the issue in Merck Sharp & Dohme Corp v Wyeth LLC (No. 3))³ , insufficiency and support are “two sides of the same coin”.

Because the term “complete enough” in the sufficiency requirement is not defined and therefore “ambiguous”⁴ then as the Court noted it is permissible to have regard to the various secondary material associated with the Raising the Bar amending legislation. That secondary material made it clear that the intention of the amendments was to harmonise the tests with the position in the United Kingdom and Europe; namely, that a patent specification must teach the skilled addressee how to perform the invention across the breadth of the claims.

Jusand’s patents in suit in Rattlejack concerned a safety system for preventing a broken longhole drill rod from falling down the drill bore hole and injuring a person in the tunnels below. The claimed invention involved a plug-like product which was inserted into a bore hole containing a broken drill rod or rods (which could weigh many hundreds of kilograms) and was designed to operate in a manner that would break the fall of any drill rods that fell down. The claims of the patents did not mention the nature of the materials from which the safety system could be made. In other words, according to the breadth of the claims, the safety system could within reason be made from any material. However, the specification only provided guidance to the skilled addressee with respect to making the safety system out of steel.

The Court gave detailed consideration to the most significant UK decision on sufficiency, that of the UK Supreme Court in Regeneron Pharmaceuticals Ltd v Kymab Ltd⁵. That case sets out a series of fundamental principles relating to sufficiency. It was concerned with transgenic mice containing a genetic region called the “variable region” which could produce human antibodies. The problem in practice was that the transgenic mice would often exhibit a decreased immune response, rendering them not particularly useful for the purpose of making human antibodies. At a very high level, the patent sought to solve that problem by claiming immune responsive mice which contained the entire human variable region and could therefore produce all human antibodies across that entire region.

However, in contrast to the breadth of the claim, the specification only taught the creation of mice which could produce such antibodies across some of the human variable region. To that end, the Court held that because Regeneron had not disclosed in its patent how to make mice which produce the full range of human antibodies (as had been claimed) it was not entitled to a monopoly for mice across the range; that is, the patent was invalid for lack of sufficiency.

One of the key reasons for that finding in Regeneron (and a central issue in Rattlejack) was the following statement from Lord Briggs who delivered the lead judgment in Regeneron:

“The requirement to show enablement across the whole scope of the claim applies only across a relevant range. Put broadly, the range will be relevant if it is denominated by reference to a variable which significantly affects the value or utility of the product in achieving the purpose for which it is to be made”.

In Rattlejack, the both the trial judge and the Full Court found that the expert evidence led to the conclusion that the claims were not limited to a safety system made from steel and consequently that its construction from materials other than steel was a plausible working of the claims.

Once it had been established that there might be a plausible range of materials from which the claimed invention could be made, Perram J then moved to identify the “essence or core” of the invention (an approach established in a post-Regeneron trial decision on sufficiency of the High Court of England and Wales in Illumina Cambridge Ltd v Latvia MGI Tech SIA)⁶. Regeneron made no reference to the concept of “essence or core”. Birss J, one of the UK’s pre-eminent patent judges, formed the view that the passage from Lord Briggs as set out above must logically be interpreted in a way where the issue is assessed having regard to the “essence or core” of the invention.

In Rattlejack, Perram J found that the invention as disclosed in the specification was a system made from steel. His Honour found the innovative step to be the conversion of downward forces from a falling drill rod into lateral braking forces and also found that the technical contribution to the art was the “taking of that idea and explaining how to use it in a safety system utilising steel”. His Honour then said that the essence or core of the invention involved a consideration of each of those concepts.

Adopting that reasoning process resulted in Perram J indicating that it was “impossible to accept [Jusand’s] submission that the material from which the safety system is to be made is irrelevant to it”. Accordingly, if the range of material options from which the safety system could be made significantly affects its utility for purpose (where that purpose is assessed by reference to the essence or core) then the range is a “relevant” one for Regeneron purposes; the caveat being that the materials which fall within the range must be able to used and implemented by a skilled addressee without undue burden.

At least in relation to a product claim, a patent’s technical contribution to the art is the product and not the inventive step. The Court noted that caution should be applied when attempting to extend that principle beyond product claims. In that context, Perram J added:

“Noting that caution, in a method claim such as the present concerned with a mechanical apparatus I would accept that the technical contribution of the patent to the art is the explanation of how to perform the method disclosed in the specification. The technical contribution to the art is not the same as the inventive step, although the inventive step may constitute an element of the contribution to the art”.

Support was given little additional consideration because, as Perram J observed, sufficiency and support are often different sides of the same coin and that was the case in Rattlejack⁷.

Whether Rattlejack introduces another non-statutory concept, namely the “essence or core” of an invention, into Australian patent common law is perhaps unclear. The preferable view might be that the concept was merely used by Perram J as a conceptual tool which might be useful to consider in connection with certain claimed inventions⁸. What differences (if any) might exist in the reasoning process between attempting to identify the ”essence or core” of the invention to the “substance of the invention” (being another non-statutory term invoked in a manner of manufacture context)? The answer to that question lies ahead.

Addisons Partner James Lawrence acted for Rattlejack Innovations.