3. Allowability of amendments under Art. 123(3)
The extent of protection conferred by a European patent is determined by the claims. Nevertheless, the description and drawings are to be used to interpret the claims.
The Protocol on the Interpretation of Art. 69, which is, pursuant to Art. 164(1), an integral part of the EPC, specifies how Art. 69 is to be interpreted.
Since, pursuant to Art. 69(1), amendments to the description and drawings will also influence the interpretation of the claims, and may therefore extend the protection conferred, any such amendments extending protection in this way are not allowable (see G 1/93).