The central limitation and revocation procedure at the EPO is a mechanism by which a patentee, after grant of the patent, can amend its patent or even revoke its own patent completely. Unlike reissue proceedings in the United States, central limitation does not reopen prosecution of the application on its merits and therefore cannot result in the patent being found invalid. Furthermore, it is not necessary for a patentee to explain why it wishes to amend or revoke its own patent.

Applications for limitation (i.e., for amendment) are examined for clarity (Article 84 EPC) and compliance with allowability of amendments (Article 123 EPC). The proposed amendment must be directly and unambiguously derivable from the application as-filed (Article 123(2) EPC), and must not result in extension of the scope of protection, i.e., cannot result in the amended claims covering something not covered by the claims as-granted (Article 123 (3) EPC).

Any amendment must result in the scope of protection being reduced (limited). It is not permissible to amend merely to resolve clarity issues or to add claims to different subject matter.

If allowed, any limitation or revocation is effective in all designated states.

There is no time limit on when an application for limitation or revocation can be filed. However, oppositions or appeals from opposition take precedence over an application to limit a patent. An application to revoke a patent during opposition or appeal proceedings will, if allowed, result in termination of the proceedings.

The central limitation procedure is a relatively quick and straightforward process for addressing known deficiencies in patent claims, particularly where litigation is contemplated in a number of designated states. The alternative is to apply to amend in each designated state, individually, which can be significantly more expensive and slow, and can result in different claim scope in different states.

Finnegan's European patent attorneys are all qualified to handle central limitation and revocation proceedings and can advise on both practical and strategic issues relating to the procedure.

Cupitt, Philip
Partner, European Patent Attorney
+44 (0)20 7864 2811

Ford, Hazel
Partner, European Patent Attorney
+ 44 (0) 20 7864 2820

Hyden, Martin
Partner, European Patent Attorney
+44 (0)20 7864 2810

Wall, Leythem
Partner, European Patent Attorney
+44 (0)20 7864 2814