No Dumb B****: 11 Trade Mark Lessons from the Katy Perry dispute

In 2009, Katy Perry’s team fired off an internal email about the Australian fashion designer who had dared to register a trade mark in her own birth name.

“Dumb b**ch. Rawr.”

Yesterday, 11 March, the High Court of Australia handed down its decision in Taylor v Killer Queen LLC [2026] HCA 5.

The Australian designer won. The global pop star pays the costs. Roar indeed!

This is the story of one of the most dramatic trade mark dispute in Australian legal history and I have distilled 11 trade mark lessons/pointers every business owner needs to take from it.

The story in 60 seconds

Katie Taylor is a Sydney fashion designer who built her label around her birth name. She had used her mark since 2007, and registered her trade mark in September 2008. At that point, Katy Perry the global pop star had never sold a single item of clothing in Australia. That did not stop her team from coming for the registration and selling ‘Katy Perry’ branded clothing through Target, Harris Scarfe and Best & Less for years, in what the trial judge later called a calculated disregard of the AU Designer’s rights.

Taylor sued in 2019. The Full Federal Court cancelled her mark in 2024. On Wednesday, the High Court restored it in a slim margin: 3 votes to 2. Despite that slim margin, there are some important takeaways from the decision and I have distilled my key 11 takeaways:

1. Famous in music ≠ famous in clothing

This is the legal heart of the decision. Katy Perry was undeniably, globally famous. But the High Court majority held that her enormous reputation lived in pop music, not in clothing. This is because she had never sold a single item of clothing in Australia before the designer’s filing date. The Full Federal Court had accepted that because pop stars commonly sell merchandise, the reputation crossed over. The High Court rejected that reasoning . Common practice is not the same as actual use. If you haven’t used it here, you don’t have a reputation here.

2. “Everyone does it” / industry trends are not enough to extend the reputation

The ‘common practice’ argument, i.e. that pop stars typically launch clothing lines, so consumers would expect it, did not survive the High Court. Trade mark law rewards actual use, not industry custom or commercial aspiration. For any business building a brand into a new category or market: registration can beat reputation.

3. Your registration has real teeth….even against a global superstar

A registered trade mark is not a filing exercise. It is a statutory monopoly. The High Court confirmed it holds even when the party on the other side is richer, more famous, and infinitely better resourced. The register means something. Use it to your advantage.

4. But the margin should make everyone uncomfortable

Three votes to two. And those 3 decisions were all separate majority judgments. 3different analytical routes to the same destination and 2 equally rigorous judges who got to the opposite answer. This is not settled law. It is a signal that the legal framework in this area remains genuinely contested. For businesses relying on registered marks: the system works. But it is not infallible.

3-2 is a slim margin. On a different bench, on a different day, this goes the other way.

5. Ten years of no confusion is not nothing… more than mere absence of evidence

The singer’s team argued that zero confusion over a decade was meaningless as the AU designer’s business was simply too small for confusion to have surfaced. The High Court rejected that. A decade of coexistence through the full arc of Katy Perry’s rise to global superstardom, with nothing emerging despite the opposing party having the benefit of discovery, was probative. Small scale does not erase your evidence. It contextualises it.

6. Can’t afford to fight? Document why. Courts will listen.

The laches/delay argument, i.e. that Taylor’s ten-year delay should cost her, failed because the court accepted she simply could not afford to litigate against a global superstar. She became aware of litigation funding in 2018 and moved promptly once she had access to it. For SMEs: financial incapacity is a legitimate reason for delay. But you need to be able to prove it. Keep a clear record of why you waited, not just that you did.

7. A shield for small businesses: the assiduous infringer doctrine

In one of the most significant developments in this decision for small business owners, Justice Steward breathed life into what is known as the assiduous infringer doctrine. His core proposition: a party that knowingly and persistently infringes your registered mark cannot then use the circumstances it created through that infringement to cancel your registration. If this reasoning takes hold — and a recent Full Court decision in Firstmac v Zip Co points the same way — it closes off one of the most dangerous plays in the big brand playbook: swamp the market, wait, then apply to cancel the registration you’ve been infringing.

You cannot burn someone’s house down and then complain about the smoke.

8. The infringer knew. And did it anyway.

From 2009, the singer’s team knew they were operating in the face of a valid Australian registration. They called it a ‘calculated risk.’ The primary judge called it ‘calculated disregard.’ The question of additional damages for flagrant infringement over many years is now back before the Full Court on remitter. The financial reckoning from this case is not yet complete.

9. A co-existence agreement is sometimes the smartest move on the board

In 2009, Katy Perry’s team offered a co-existence arrangement. Taylor declined. The Full Federal Court later observed it would have been ‘an excellent outcome for both parties.’ Taylor ultimately won… but after 15 years of back and forth, enormous personal cost, and a 3-2 squeaker that could have gone either way.

Before you go to war over a brand conflict, ask whether a well-drafted boundary might serve you better than a verdict.

10. This case is not actually over

Three grounds go back to the Full Federal Court on remitter including whether Kitty Purry Inc owes additional damages for years of flagrant infringement. The AU designer has her mark back. But the full financial story of this dispute is still being written. Watch the remitter closely.

11. The system worked. But only just.

Katie Taylor did everything right, registered, used, documented, defended. It still took 15 years, a High Court appeal, litigation funding, and a fragmented 3-2 majority to protect what was hers. The trade mark register is only as strong as the rights you build on top of it. And your willingness to defend them.

The register is only as strong as the rights you build on top of it and the perseverance you demonstrate to fight it.

The lesson for every business owner:

Register early. Use your mark. Document everything. Act when you see infringement or document clearly why you can’t. And get advice before you build a brand, not after someone bigger has come for it.

The law, properly applied, is on your side. Even if it sometimes takes 15 years to prove it.

Contact: Aparna Watal (Aparna.Watal@halfords.com.au)

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