Patents And Estoppel In Australia | What The Orikan V VMS Rulings Means For Your Next Dispute

If you opposed a patent and didn’t raise every invalidity ground available to you, does that limit your options later if you’re sued for infringement? Two recent Federal Court decisions, arising from the same long-running dispute over parking-sensor technology, settle the question: not necessarily.

The Court has confirmed that a party defending an infringement claim may be able to raise new invalidity grounds it left out of an earlier opposition proceeding. It may also in some cases, be able to re-run a ground like insufficiency on a different factual basis. What it can’t do is re-argue claim construction findings already made – those follow the parties into the next fight, win or lose.

Since the standard of proof in opposition proceedings was amended to “balance of probabilities” in 2013 with the Raising the Bar amendments, there had been some uncertainty as to the effect of earlier opposition proceedings on later infringement and revocation proceedings.

As a result of these proceedings, giving rise to the Orikan v VMS rulings, it has now been clarified that:

1. A party defending against patent infringement is not precluded from raising invalidity grounds in a cross-claim for revocation merely because it could have, but did not, raise those grounds in earlier opposition proceedings. The same would not necessarily be the case where the party initiates revocation proceedings against the patentee.
2. At least the ground of insufficiency can be re-agitated where it rests on a different factual basis; an earlier finding that a patent was sufficient because feature A was adequately disclosed does not prevent a later argument that the patent is not sufficient because feature B was not disclosed.
3. Findings on claim construction made in Federal Court opposition proceedings that were legally indispensable to the earlier decision will bind parties in subsequent proceedings. Even non-essential construction findings are likely to be followed unless clearly wrong.

The dispute

The case concerned underground parking technology. Orikan (and its predecessors) alleged that VMS infringed Australian Patent No. 2013213708 entitled “Vehicle Detection” by operating its Parking Overstay Detection System (PODS). The filing date was 28 August 2008.

The case concerned underground parking technology. Orikan (and its predecessors) alleged that VMS infringed Australian Patent No. 2013213708 entitled “Vehicle Detection” by operating its Parking Overstay Detection System (PODS). The filing date was 28 August 2008.

VMS denied infringement and cross-claimed for revocation. VMS also asserted a prior use defence, contending the patent was entitled only to a priority date of 7 August 2013 – after VMS had already been exploiting PODS.

The interlocutory decision | 2023

Before trial, Orikan sought to shut out several of VMS’s invalidity grounds on the basis that they could have been raised in the Federal Court opposition proceedings between VMS and Orikan predecessor, SARB Management Group, in 2020¹.

The case concerned underground parking technology. Orikan (and its predecessors) alleged that VMS infringed Australian Patent No. 2013213708 entitled “Vehicle Detection” by operating its Parking Overstay Detection System (PODS). The filing date was 28 August 2008.

After this decision, VMS amended its cross claim and among other changes, added the ground of lack of sufficiency.

The substantive decision | 2026

At trial, the Court found Orikan had not established infringement and that none of the asserted claims were entitled to a priority date earlier than 7 August 2013. VMS’s prior use defence therefore also succeeded.

Each of Orikan and VMS was estopped from contesting the construction findings made in the Opposition Proceedings.

On VMS’s cross-claim, claims 1 to 24 of the Patent were found invalid on two grounds.

Lack of sufficiency

Orikan argued VMS was estopped from raising insufficiency because that ground had been decided against VMS in the Opposition Proceedings.

Applying Blair v Curran (1939) 62 CLR 464, his Honour held that issue estoppel extends only to matters necessarily established as the legal foundation of an earlier judgment. Because VMS advanced a different factual basis for the ground of lack of sufficiency, it was not estopped from raising this ground.

As to lack of sufficiency, his Honour accepted VMS’s expert evidence that implementing the vehicle detection and violation determination step to the required accuracy would demand ingenuity beyond the skill of the person skilled in the art. The specification was therefore insufficient.

This finding also defeated the claim to an earlier priority date, since the corresponding provisional, PCT, and parent applications contained substantially the same (inadequate) disclosure.

Best method

Consistent with the Full Court’s recent confirmation in NOCO Company v Brown and Watson International Pty Ltd [2026] FCAFC 44, the relevant date for assessing the patentee’s knowledge of the best method is the filing date of the complete specification in suit – here, 7 August 2013 – not the earlier PCT or parent filing date.

Internal Orikan specifications predating that date revealed a best method that had not been disclosed, and the ground was made out.

Practical takeaways

It remains important for those seeking to challenge the grant of a patent in opposition proceedings to carefully consider the grounds of opposition when those proceedings are before the Federal Court.

Nonetheless, if the challenging party is later sued for infringing the patent, it may be possible to rely on different grounds as well as, at least in some cases, the same grounds where there is a different factual basis. The parties will remain bound by findings on construction.

How we can help

Spruson & Ferguson Lawyers acted for VMS throughout both proceedings – from the 2023 interlocutory decision through to VMS’s win at trial in 2026.

If your business is navigating a long-running IP dispute, or weighing up how hard to fight at the opposition stage knowing it might not be the last word, we’ve done this before and can help you think it through early.

1. Vehicle Monitoring Systems Pty Ltd v SARB Management Group Pty Ltd [2020] FCA 408 – Opposition Decision

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.