Why a 2025 Patent Case is a Must-Read on Split Decisions and Judicial Precedent

Aristocrat Technologies Australia Pty Ltd v Commissioner of Patents [2025] FCAFC 131

Introduction: A Decision Beyond Patent Law

On 16 September 2025, The Full Court of the Federal Court of Australia delivered a very interesting judgment in the matter of Aristocrat Technologies Australia Pty Ltd v Commissioner of Patents [2025] FCAFC 131.

From my perspective, not being a someone who practices in Patent Law, I am specifically referring to the Court’s discussion regarding the effect of split decisions in High Court and the test to be applied by appeal courts in order determine whether to depart from an earlier decision from the same Court. This is not to say that the decision is not important from Patent Law perspective only that it’s not something I can speak to.

A Complicated Procedural History

A reason why this case is particularly interesting is because of the procedural history of the matter. In simple terms, succinctly put, history of the matter prior to reaching this machination of the Full Court was: Decision of the Commissioner of Patents, Burley J allowed the appeal of Aristocrat; by a 2:1 majority, the Full Court of Federal Court of Australia constituted by the majority of Middleton and Perram JJ allowed the appeal of the Commissioner with Nicholas J in dissent (meaning no disrespect I call this Court the “First Bench”); in a split decision, 3 judges of the High Court (Keifel CJ, Gageler and Keane JJ) dismissed the appeal whereas the other 3 judges (Gordon, Edelman and Steward JJ) would have allowed the appeal; the matter was remitted to Burnley J to determine “in light of the light of the Full Court’s reasons…”, which his Honour did – again in favour of the Commissioner’s position; leave was then granted in favour of Aristocrat to appeal from that decision; an application by Aristocrat to move the whole matter to the High Court was unanimously reject by 7 member bench of the High Court; Aristocrat then proceeded with its appeal to the Full Court. The bench this time consisted of Beach, Rolfe and Jackman JJ – I will call them, again without intending any disrespect, the “Second Bench”.

The Precedential Effect of a Split High Court

The above process presented the Second Bench with some quite interesting problems. First and foremost, was Burnley required to follow the reasoning Middleton and Perram JJ of the First Bench (as his Honour did) or that of Keifel CJ, Gageler and Keane JJ in the High Court. Alternatively, was it possible to find a unified thread from both the totality of the High Court judgement irrespective of whether the reasons stated that the appeal should be dismissed or allowed (was it seriously considered dicta). The Second Bench determined that Burney J was incorrect to follow the majority reasons of the First Bench. In doing so, the Second Bench explained that s.23(2)(a) of the Judiciary Act was an “expedient” that facilitated the disposal of a case before the High Court where the Court was evenly split such that if the majority decision of the First Bench that had to be followed.

In forming this view, the Second Bench noted that, as opposed to the split decision of the High Court, there was a majority decision in the First Bench in the form of the reasons of Middleton and Perram JJ and, by the doctrine of precedent, Burney J was bound to apply that those reasons. Aristocrat initially tried to avoid this outcome but ultimately decided to seek leave to amend the grounds of appeal – which I will discuss below. Of particular note is the Second Bench’s discussion on the well-known decision of Farah Constructions Pty Ltd v Say-Dee Pty Ltd [2007] HCA 22; (2007) 230 CLR 89 regarding the obligation on intermediate appellant courts to “not depart from long-established authority and seriously considered dicta of a majority of the High Court.” Following Harvard Nominees Pty Ltd v Tiller [2020] FCAFC 229; (2020) 282 FCR 530 (Lee, Anastassiou and Stewart J), the Second Bench noted that “not only is that the better reading of the passage in Farah, but dicta of a majority of the High Court would otherwise enjoy the same precedential status as rationes.” There is a good explanation as to why this is so but something I am going to delve into in a short point like this.

When Can an Appeal Court Depart from its Own Decisions?

Ultimately, Aristocrat succeeded on the amended ground of appeal by which they asked the Second Bench to reconsider the First Bench. Again, there is some excellent commentary from the Second Bench as the circumstances when it is appropriate for Full Federal Court to depart from the judgment of another Full Federal Court. As part of that discussion, the Court noted that the Full Federal Court was not strictly bound by its own previous decisions – citing Transurban CityLink Ltd v Allan [1999] FCA 1723; (1999) 95 FCR 553. The Court also noted that the “plainly wrong” test for determining when a departure is appropriate has been subject to much criticism, had led to some unintended and irrational consequence and (importantly) was not attest that had been laid down by the High Court. Ultimately, the Second Bench that the appropriate test was that “the Full Federal Court should depart from an earlier Full Federal Court decision only where there is a compelling reason to do so.”

A Compelling Reason for Departure

The Court then set out the reasons why there was a compelling reason to do so in this case. A critical part of that reasoning was the fact that all six members of the High Court had criticised the “two-stage test” adopted by the First Bench.

Conclusion: A Reminder for All Practitioners

Aside from the importance of the decision on question of precedent and the impact of split decision of the High Court, this case serves a reminder that it is always worth browsing decisions of the High Court and those of appellant courts irrespective of the practice area into which a case may fit because there are plenty of occasions where a case, which appears to be in an area where you do not practice, will have much broader application.