United Kingdom: A matter of opinion

Managing IP is part of Legal Benchmarking Limited, 1-2 Paris Gardens, London, SE1 8ND

Copyright © Legal Benchmarking Limited and its affiliated companies 2026

Accessibility | Terms of Use | Privacy Policy | Modern Slavery Statement

United Kingdom: A matter of opinion

The UKIPO has long provided the means for any third party to obtain an independent opinion on questions of validity and infringement in relation to granted UK and EP(UK) patents. More recently this service has been extended, for example by allowing additional grounds of invalidity to be raised, leading to a surge in its popularity among clients operating in the UK.

Any person may request the UKIPO to provide an opinion on validity or infringement of a UK or EP(UK) patent. However, opinions are typically requested by a patent holder, an exclusive licensee of the patent or a third party for whom a patent poses an infringement risk.

When filing any request for an opinion, it is essential to set out the evidence and arguments that support your position. For example, when arguing for invalidity, any request for an opinion should include detailed reasoning in relation to each ground of invalidity raised while highlighting relevant prior art documents. Alternatively, when arguing for an opinion of infringement, it is important to set out the facts relating to any potentially infringing products and acts.

While any opinion issued is non-binding, the position of the UKIPO may assist in formulating an overall commercial strategy surrounding the patent right in question, and strengthen a position in mediation. Additionally, the opinion system offers a further advantage in that a finding of patent claim invalidity may cause the UKIPO to begin the process of revocation in the UK. This process is only undertaken on patents the UKIPO deem to be clearly invalid.

The UKIPO may begin revocation proceedings in relation to both UK and EP(UK) patents. In the case of EP(UK) patents, such revocation proceedings will only affect the UK and will not be Europe wide.

Overall, the opinions service offered by the UKIPO is a useful commercial tool, offering a means of obtaining an independent opinion as to any aspect of patent validity or infringement. Additionally, in the clearest cases of invalidity, the UKIPO opinion service is an attractive option where rapid, cost-effective revocation of a competitor's patent is desired.

Chapman

Helga Chapman

Chapman + Co

Patent and Trade Mark Attorneys

Chapman IP, Kings Park House, 22 Kings Park Road

Southampton SO15 2AT, UK

Tel: +44 (0) 23 8000 2022 

info@chapmanip.com  

www.chapmanip.com

more from across site and SHARED ros bottom lb

More from across our site

New partners, from biotech company Leyden Labs and Novartis, take the total number of partner hires to 12 since the firm took on external investment in late 2024
Labelled the ‘largest law firm merger in history’, the new outfit could also spell an opportunity for US clients to capitalise on Hogan Lovells' UPC expertise
Andy Lee and Amy Brooks of Brandsmiths explain how the firm secured a win for Peppa Pig over rival children’s character Wolfoo, in a case that centred on copied audio clips
Pedro Moreira outlines proposals by INPI that look set to open a discussion regarding biological materials, extracts, sequences, genetically edited plants, and computer programs
The combined firm, which has a newly appointed IP partner in London, brings together more than 3,500 practitioners across 52 offices, with flagship hubs in Seattle, London, Sydney and New York
A host of SEP-rich law firms, both leading arguments and as intervenors, are set to feature in the UK Supreme Court’s third FRAND episode, though one ground of appeal has been settled
Law firms are investing in generative engine optimisation and boosting their online presence in the hope of gaining a new client base
A decision on a licensing rate payable by Warner Bros and Paramount, and a survey outlining UK businesses’ lack of IP preparation ahead of launching abroad, were among other major talking points
A fresh wave of deals highlights why investors favour IP firms and why independent outfits may soon have to rethink their strategy
King & Spalding has now hired 15 partners from Winston Taylor and legacy firm Winston & Strawn in offices spanning Texas, San Francisco, and Chicago
Gift this article