
Mark Earnshaw
Executive Director
Best-in-class representation and guidance for oppositions and appeals at the European Patent Office (EPO), tailored for US patent owners.
We help US-based clients navigate the EPO opposition and appeal process efficiently, strategically and cost-effectively.
You could be seeking to challenge third-party patent rights, thereby clearing the way for freedom to operate within Europe.
Alternatively, you may be defending your own patent during opposition proceedings initiated by a third party.
Listed as one of Europe’s leading patent law firms, we are perfectly placed to guide you through the entire process.
We bring deep expertise advising on complex oppositions and appeals across many specialist areas, including engineering, chemistry and materials, life sciences, and technology and media.

An EPO opposition is a procedure allowing a third party to challenge the validity of a granted European patent.
For US-based companies, opposition proceedings can be a powerful tool for securing freedom to operate in Europe. They are also a cost-effective alternative to litigation in national European courts, with a single procedure covering all EPC states.
Anyone can file an opposition to a patent within nine months of the date of the grant being published. Proceedings can lead to the patent being maintained as granted, amended or revoked.
Each case is different, which is why we always place EPO oppositions in their broader commercial context. Some may support a licensing or enforcement strategy, whilst others may be a make-or-break battle over a core technology.
Your case may also form part of a larger dispute involving the Unified Patent Court or a national court or office. We can help you coordinate across all of these, so each one works towards the same commercial goal.

The EPO offers a centralised route to challenge a European patent across all contracting states, rather than having to fight multiple battles in national courts.
Whether you’re the patentee or the opponent, winning a case requires a meticulous approach, blending legal and advocacy skills.

We support US-based clients of all shapes and sizes with EPO oppositions and appeals, including start-ups, SMEs, large corporations and law firms.
With two US liaison offices and regular attorney travel, we work closely with founders, in-house counsel and C-suite executives to build a genuine understanding of your business and commercial goals.
We offer specialist docketing and search teams based across US time zones, alongside 24/7 advanced client portal access.
Our added value is acting as a seamless extension of your IP capabilities: a single point of contact and one-stop service for all your UK and European IP coordination and strategy.
Our team brings a deep knowledge of EPO rules and procedures – message us if your query isn’t covered.
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Protect your patents and effectively challenge competitors at the EPO. Our support in oppositions and appeals ensures your rights are defended.