The claims fees must be calculated on the basis of the number of claims contained in the application in the version that is, in accordance with the indications in Form 1200, to be taken as the basis for processing in the European phase (see
point 500). However, where the number of claims changes as a consequence of a later (further) amendment filed before expiry of the time limit set in the
Rule 161 EPC/
Rule 162 EPC communication, that number is to be used as the basis for calculating the amount of the claims fees to be paid. The Rule 161/162 communication sets a six-month time limit for payment of any claims fees not yet paid (see
point 501).