The Unified Patent Court has now been operating for over two years. What started with considerable uncertainty has settled into something more significant than many predicted and UK businesses with European patents need to understand what it means for them.
What is the UPC and where does the UK stand?
The Unified Patent Court is a specialist patent court covering the EU member states that have ratified the UPC Agreement. It opened on 1 June 2023 and allows patent holders to bring a single infringement action covering all participating states simultaneously, rather than pursuing separate national proceedings in each country.
The UK is not a member. Brexit removed the UK from the system before it launched, and there is no current prospect of rejoining. UK-registered patents and UK patent disputes remain subject to the UK courts as before.
However and this is the point that many UK businesses miss the UPC’s jurisdiction does not stop at the UK border in every respect.
The long-arm jurisdiction question
The most significant development of 2025 was the UPC’s confirmation that it can decide on patent infringement in the UK, even though the UK is not a member, provided the defendant is domiciled in a contracting member state.
This was confirmed in the Fujifilm v Kodak decision at the Dusseldorf Local Division in January 2025. In short, a European company that believes a UK business is infringing their Unitary Patent can bring a UPC action and obtain a ruling that covers UK activity. The UPC’s Court of Appeal has consistently taken an expansive view of the court’s jurisdiction, and further developments in this direction are expected through 2026.
For UK businesses operating in European markets or competing with European patent holders, this is a material change in the risk landscape.
How the UPC is being used in practice
The filing data from the EIP UPC Review 2025 tells a clear story. By the end of 2025 the court had received over 1,000 cases at first instance, including 536 infringement actions, 91 revocation actions and 141 applications for provisional measures. More than half of all infringement actions ever filed were filed in 2025 alone, with a marked acceleration in the second half of the year.
This is not a court finding its feet. It is a court gaining momentum. Infringement actions now represent nearly 70% of all filings, and provisional measures — urgent interim injunctions — are a significant and growing part of the workload.
The language of proceedings has also shifted. English has overtaken German as the most commonly used language, accounting for close to two thirds of new filings by the end of 2025. For UK businesses and their advisers, this removes one of the practical barriers to engaging with UPC proceedings.
What this means for UK patent holders
If your business holds European patents registered through the European Patent Office and validated in EU member states you now have two important options.
You can opt out of the UPC system for your existing patents, keeping disputes in the national courts you are familiar with. Or you can remain within the system and use the UPC as a powerful single-action enforcement tool across all participating states.
The opt-out decision is not permanent and can in some circumstances be reversed, but it needs to be made actively. Many UK patent holders have not given this sufficient thought.
If you hold Unitary Patents the new single patent covering all participating UPC states there is no opt-out available. These are subject to the UPC’s jurisdiction by design.
What this means for UK businesses without European patents
If your business does not hold European patents but operates in European markets, the UPC makes you more exposed to enforcement actions from European competitors, not less. A single action in a UPC Local Division can now produce an injunction covering 17 EU member states simultaneously. The cost and speed of pan-European enforcement have both improved significantly for well-resourced patent holders.
The acceleration in filings through 2025 suggests that more patent holders are becoming confident in using the system. UK businesses that compete with European IP-rich companies should be aware of this.
The insurance angle
Whether you are enforcing European patents through the UPC or defending a UPC action with potential UK effect, the financial exposure of cross-border patent litigation is significant. A UPC infringement action covering multiple jurisdictions is not a cheap proceeding to defend.
IP insurance covers the legal costs of defending patent infringement allegations and enforcing your own rights, including proceedings in the UPC. For UK businesses with European patent exposure, ensuring that cover is in place before a claim arrives rather than after has never been more relevant.
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This article is provided for general information purposes only and does not constitute legal advice. Readers should seek independent legal advice on their specific circumstances before taking any action.
This article is provided for general information purposes only and does not constitute legal advice. Readers should seek independent legal advice on their specific circumstances before taking any action.
