the maintenance of a patent in an amended form may also be regarded as a success. The opposition has effect on all designated states in the European patent. Decisions by Opposition Divisions, like any other final decisions of first instance divisions, are appealable. A decision of the EPO to revoke a European patent is final (when the opportunity to appeal before the EPO is exhausted), which makes the opposition proceedings at the EPO especially attractive for opponents. In contrast, a decision of the EPO not to revoke a European patent (the decision instead maintaining the patent as granted or in an amended form) leaves the way open for revocation by the national court. The EPO decision does not create an estoppel precluding a subsequent challenge by an unsuccessful opponent at the national level (at least before the English courts). The validity of a European patent can be scrutinised both at the national level, before a national court, and at the international level, before the European Patent Office during opposition. The same is not true for infringement proceedings, upon which national courts exercise exclusive jurisdiction. Apportionment and fixing of costs Each party to the opposition proceedings normally bears the costs it has incurred, unless the Opposition Division (or, in appeal proceedings, the Board of Appeal under ), for reasons of equity, orders a different apportionment of costs. For example, in case T 1306/05, a highly relevant document had been lately filed, without any valid justification, by the opponent during the oral proceedings before the Board of Appeal, thus rendering useless both the oral proceedings and the patent proprietor preparation thereto. A different apportionment of costs has been ordered by the Board of Appeal. The patent proprietor has requested, under and , about €26,000 to be paid by the opponent. During first instance proceedings, a decision on apportionment of costs forms part of the main decision of the Opposition Division. The main decision however only deals with the obligation on the party or parties concerned to bear costs (apportionment), whereas the actual amounts to be paid by one party to another are dealt with in another decision, namely a decision on the award (fixing) of costs. A decision on the award of costs is taken only after a decision apportioning the costs has been taken and if a request is submitted to that effect. When a Board of Appeal has to rule