The Enlarged Board of Appeal (EBA) of the European Patent Office (EPO) has now issued its long-awaited decision in case G 1/23 (case details provided in our previous article here). As a result of G 1/23, European patent law is now more closely aligned with the “on-sale bar” in US patent law.
Previously in Europe, it had been possible for Applicants to sell products on the market and not have such sales prevent future patenting, if the products were irreproducible by a skilled person at the date of patent filing. However, G 1/23 has changed this. Now, a product that is made public by use, sale, description or otherwise can invalidate a later filed European patent, regardless of whether its composition or internal structure could have been analysed and reproduced at date of applying for the European patent.
Crucially, however, this is not entirely the same as the US on-sale bar. In particular, confidential sales (for example, suppling a sample to a customer in exchange for a fee) would still not qualify as prior art in Europe under this new approach, since the sale is not public.
Practice points
The decision reinforces the importance of filing a patent application before making an invention available to the public, even when the invention cannot be analysed or reproduced from the publicly disclosed product.
It also increases the importance of validly claiming priority in the circumstance that a public disclosure is made after a priority filing but before filing the priority claiming, European application. It is more important than ever to file a complete, high quality priority application, to protect the validity of any subsequent claims to priority.
Phil Horler
Electronics, Computing & Physics group
This publication is a general summary of the law. It should not replace legal advice tailored to your specific circumstances.
© Withers & Rogers LLP July 2025
