A catchy name and a fast start built a billion-dollar lending business — but neither could rescue the trade mark when it mattered most. Australia’s High Court has now confirmed that the “honest concurrent use” defence to trade mark infringement is judged at the moment a business first uses the mark, not years later when it is sued or when the matter reaches trial. In the dispute between Zip Co and Firstmac, Zip adopted the ZIP brand without knowing of Firstmac’s earlier registration — but within months, IP Australia’s examination reports put Zip squarely on notice of the conflict. Zip gave those warnings cursory attention, took no advice, and pressed ahead. Years and 1.3 million customers later, the Court held that Zip had failed to prove it acted honestly at first use, and commercial success could not retroactively cure that. The burden sits with the user to affirmatively establish honesty, and knowledge of a prior mark weighs heavily against you.

The strategic lesson is sharper than it first appears. Brand clearance is not a formality to be tidied up after launch — it is a decision point that fixes your legal position for the life of the mark. An adverse examination report is not noise; it is the moment your risk profile changes, and how you respond becomes part of the evidentiary record you may one day need to rely on. Ignore it, or pivot to attacking the incumbent’s registration instead of engaging with the problem, and you signal awareness of the very impediment you later have to disprove.

For founders and in-house counsel, the discipline is simple: clear the name before you commit, document the genuine basis for believing there is no conflict, and treat regulator warnings as live strategic intelligence rather than paperwork. The businesses that scale safely are the ones that get the IP groundwork right at the starting line — because that is exactly where the law will look.

The full decision, Zip Co Limited v Firstmac Limited [2026] HCA 16, is worth reading: https://www.austlii.edu.au/cgi-bin/viewdoc/au/cases/cth/HCA/2026/16.html