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European Patent Convention (EPC 1973)

A revised version of the European Patent Convention entered into force on 13 December 2007. The provisions of the revised Convention apply unless the transitional provisions provide for the applicability of the EPC 1973.

Article 123 89


Art. 100, 138
R. 2, 7, 16, 41, 51, 57, 57a, 58, 86, 87

(1) The conditions under which a European patent application or a European patent may be amended in proceedings before the European Patent Office are laid down in the Implementing Regulations. In any case, an applicant shall be allowed at least one opportunity of amending the description, claims and drawings of his own volition.

(2) A European patent application or a European patent may not be amended in such a way that it contains subject-matter which extends beyond the content of the application as filed.

(3) The claims of the European patent may not be amended during opposition proceedings in such a way as to extend the protection conferred.

89 See decisions/opinions of the Enlarged Board of Appeal G 2/88, G 3/89, G 11/91, G 1/93, G 7/93, G 2/95, G 2/98, G 1/99, G 1/03, G 2/03 (Annex I).

Cross-reference list
Art. 123 Art. 123