Can third parties access files in nullity proceedings?

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

Can third parties access files in nullity proceedings?

Sponsored by

maiwald-logo-cropped.PNG
Stack file folders with documents on background

In the present case (X ZR 14/20), the German Federal Court of Justice again dealt with the question to what extent a third party who is not party to the nullity proceedings should be granted access to the files of the nullity proceedings.

If a party is targeted with an infringement action, the validity of the patent in suit is usually targeted with a parallel nullity action. In this case, the pleadings from the infringement proceedings are usually also introduced into the nullity proceedings in order to inform the nullity senate about the interpretation of the claim features discussed in the parallel infringement proceedings and to prevent diverging interpretations as far as possible.

Pursuant to Section 99 paragraph 3 of the German Patent Law (PatG), anyone may request inspection of the files of nullity proceedings. Only in circumstances where the patent proprietor can demonstrate a conflicting interest can inspection of the files be restricted or refused. Moreover, the third party does not have to show a legitimate interest in the inspection of the files. As the German Federal Court of Justice states, this means in practice that the inspection of the files of the nullity proceedings is basically freely available.

On the other hand, according to Section 299 paragraph 2 of the German Code of Civil Procedure (ZPO), a third party may only be granted access to the files of the infringement proceedings if the third party can substantiate a legal interest. Such a legal interest may, for example, be that the third party requires information in order to pursue its own rights or to defend itself against claims.

In the present case, the question therefore arose for the German Federal Court of Justice whether, in light of the stricter provision of Section 299 paragraph 2 of the ZPO, the inspection of files in nullity proceedings is to be restricted or whether the stricter standards of Section 299 paragraph 2 ZPO are also to be applied to the inspection of files in nullity proceedings. In other words, whether a third party should also receive the pleadings from the parallel infringement proceedings without further ado within the framework of the inspection of the files in the invalidity proceedings.

As was to be expected, the German Federal Court of Justice answered this question to the effect that inspection of the files in nullity proceedings is subject to the rules of Section 99 paragraph 3 PatG and that no stricter requirements have been or are indicated here.

Therefore, only those documents are to be excluded from the inspection of files in the nullity proceedings, with regard to which the parties to the nullity proceedings can substantiate an opposing interest worthy of protection. Such a conflicting interest may arise, for example, from the fact that the documents contain detailed explanations of the business relationships of the parties involved (cf. also BGH, GRUR 1972, 441, 442 – Inspection of files IX). In any case, it is not sufficient to point out that the subject matter of the proceedings in infringement proceedings is subject to the provisions of Section 299 paragraph 2 of the German Code of Civil Procedure.

In practice, the parties should therefore be aware that a third party could obtain inspection of the infringement proceedings by way of the inspection of files in the invalidity proceedings. As this is partly already common practice, it is therefore advisable to separate certain factual issues in the infringement proceedings and to state them in different parts of the pleadings. In this case, it is possible to file only the parts of the pleadings relevant for the nullity proceedings in the nullity proceedings.

more from across site and SHARED ros bottom lb

More from across our site

News of Health Hoglund joining Sisvel and the Delhi High Court staying a $2.2 million decree in favour of Philips were also among the top talking points
The firm is continuing its aggressive IP hiring streak with the addition of partner Matthew Rizzolo
Pantech counsel Shogo Matsunaga speaks exclusively to Managing IP about how his team proved Google’s unwillingness, and ultimately secured a landmark SEP settlement
New partners, including the firm’s first female head of a department, are eyeing a deeper focus on client understanding
Chunguang Hu of China PAT explains why his ‘insider’ experience as a patent examiner benefits clients and why he wants to debunk the myth that IP has limited value in China
Essenese Obhan shares his expansion plans and vision of creating a ‘one-stop shop’ for clients after Indian firms Obhan & Associates and Mason & Associates joined forces
From AI and the UPC to troublesome trademarks in China, experts name the IP trends likely to dominate 2026
Colm Murphy says he is keen to help clients navigate cross-border IP challenges in Europe
With 2025 behind us, US practitioners sit down with Managing IP to discuss the major IP moments from the year and what to expect in 2026
Large-scale transatlantic mergers will give US entities a strong foothold at the UPC, and could spark further fragmentation of European patent practices
Gift this article