High Court of Australia refuses special leave in Aristocrat: what this means for computer-implemented inventions

One of the biggest issues in Australian patent law over the past decade has been the criteria for eligibility of computer-implemented inventions (CIIs) for patent protection. The long running dispute between Aristocrat Technologies Australia Pty Ltd and the Commissioner of Patents is a case in point, the latest (and final) development in which unfolded last week.

Background

In a previous post (IPKat), this OzKat outlined the background to the dispute and the development that the Full Federal Court of Australia had found in favour of Aristocrat (see Aristocrat Technologies Australia Pty Ltd v Commissioner of Patents [2025] FCAFC 131). In doing so, the Full Court recalibrated (in favour of patentees) the test for patent-eligibility of CIIs previously set forth by the Full Court. Despite this development, the Patent Office made minimal updates to its Patent Manual of Practice and Procedure, and instead sought Special Leave to appeal the decision to the High Court.

Latest development

On 5 February 2026, the High Court unanimously refused the Commissioner's application for Special Leave, stating:

CII Kat

In light of the background to this application, there is insufficient reason to doubt the correctness of the decision of the Full Court. A grant of special leave to appeal is not in the interests of the administration of justice in circumstances in which that Full Court applied established principles concerning the assessment of manner of manufacture and reached a unanimous and clear conclusion as to characterisation. …

In deciding whether to grant Special Leave, the High Court has regard to factors such as whether the application relates to an important question of law, is a matter of public importance beyond the facts of the case, and whether there is inconsistency in judgements below. The High Court does not typically deliver substantive reasons for its findings in Special Leave Dispositions, as was the case here.

Consequences

In light of the refusal of Special Leave, the Full Court's decision stands as the prevailing authority on this issue. The test for patent-eligibility endorsed in that decision is to ask whether:

… properly characterised, the subject matter that is alleged to be patentable is: (i) an abstract idea which is manipulated on a computer; or (ii) an abstract idea which is implemented on a computer to produce an artificial state of affairs and a useful result.

Of course, patent eligibility remains a threshold inquiry, and claims must still satisfy the traditional requirements of novelty and inventive step.

What next?

It remains to be seen whether the Patent Office will modify its practice (and its Patent Manual) in view of the High Court's refusal to grant Special Leave. A CII Task Force – assembled in 2025 by FICPI Australia and supported by the Institute of Patent and Trade Mark Attorneys of Australia (IPTA), as well as various practitioners operating in the CII space – has proposed amendments to the Patent Manual. These amendments have been endorsed by various industry representatives, and will hopefully form the framework for examination guidelines moving forward.