Ruling on signature validity in patent application assignments

Managing IP is part of Legal Benchmarking Limited, 4 Bouverie Street, London, EC4Y 8AX

Copyright © Legal Benchmarking Limited and its affiliated companies 2025

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

Ruling on signature validity in patent application assignments

Sponsored by

inspicos-400px recrop.jpg
contract-3002431.jpg

Edward Farrington of Inspicos suggests what measures can be taken to ensure the requirements of patent application assignments are fulfilled after a ‘text string’ signature was declared invalid

The transfer of a patent application from one party to another before the EPO is governed by Article 72 of the European Patent Convention (EPC). This stipulates that an assignment of a European patent application shall be made in writing and shall require the signature of the parties to the contract.

A decision of the EPO president, published in the Official Journal of the EPO (OJ EPO, 2021, A42) in May 2021, allowed signatures on documents to be:

  • In the form of an enhanced electronic signature;

  • A reproduction of the signature (facsimile signature); or

  • In the form of a string of characters, preceded and followed by a slash (/) sign (a so-called text string signature).

Ruling on signature requirements

A decision by the Legal Board of Appeal – J5/23 – in September 2023 studied the signature requirement when a patent application is transferred under Article 72 of the EPC. The applicant in J5/23 had filed an assignment document in which one party had signed using a text string signature.

The Legal Board of Appeal studied the Vienna Convention on the Law of Treaties, and definitions of the term ‘signature’ in the three official languages of the EPO. The board found that the term ‘signature’ in Article 72 of the EPC should be understood as requiring the parties to “put their names on the assignment contract in a distinctive manner”. It also construed the signature requirement as a requirement to provide handwritten signatures, resulting in an unambiguous formal requirement.

The signature on the assignment on file, which was in the form of a text string signature, was therefore deemed not to fulfil the requirements of Article 72 of the EPC, and thus the assignment was invalid.

Additionally, the Board of Appeal found that a decision of the president of the EPO from 2021 was not concerned with assignments, and had no bearing on the case in question.

Key takeaway for patent applicants

It is therefore strongly recommended that when patent applications are to be assigned, copies of the assignment are printed, signed, and scanned, to guarantee that they meet the requirements of Article 72 of the EPC.

more from across site and SHARED ros bottom lb

More from across our site

The England and Wales appeals court handed down its judgment just seven working days after hearing the trademark dispute involving pharma company Merck
A host of law firms from across Europe and beyond helped bring the streaming technology dispute to a close
Hugues Derème, director general of the Benelux IP Office, unveils his vision for the region, how to improve IP awareness, and use of AI
A copyright win for AI firm Anthropic and a new executive order against law firm Jenner & Block were also among the top talking points this week
A principal at Schwegman Lundberg & Woessner explains how AI tools, including DeepIP, can position the firm to help clients
The firm explains why AI-empowered data analytics could make it a more efficient advocate for its clients
Penelope Aspinall, of IP wellbeing charity Jonathan’s Voice, explains why managers should take a three-tiered approach to looking after workers’ mental health
Heath Hoglund talks about the value proposition of patent pools and why it went ahead with its first-ever series of pool meetings in China
Ryan Richardson, Chris O’Brien, and Jean Selep of Sterne Kessler analyse the treatment of SEPs at the UPC and ITC and highlight why SEP holders and implementers should be mindful of current developments in both forums
A ruling concerning the UPC’s jurisdiction, questions over costs transparency, and a missed deadline by Amazon were among the top talking points this fortnight
Gift this article