In the case underlying G 1/13 (OJ 2015, A42) an opposition had been filed by a company which subsequently, under the relevant national law governing the company, for all purposes had ceased to exist. However, the company was subsequently restored to existence under a provision of that governing national law, by virtue of which the company was deemed to have continued in existence as if it had not ceased to exist. The Enlarged Board held that the EPO had to recognise the retroactive effect of that provision of national law. Thus, where a valid appeal was filed in due time in the name of the non-existent opponent and the restoration of the company to existence with retroactive effect took place after the expiry of the time limit for filing the notice of appeal under Art. 108 EPC, the board of appeal had to treat the appeal as admissible. The Enlarged Board referred to the clearly established principle under the EPC that national law should be referred to in order to determine whether a legal entity existed or had ceased to exist, and had capacity to act. The Enlarged Board also considered that the EPO should follow national law as regards the deemed retrospective existence of such a legal entity. This was merely to apply the general principle that such issues are the exclusive concern of national law.

In T 796/12 the patent proprietor raised the objection that company Z, which was registered as the appellant (opponent), had been dissolved as a result of a bankruptcy procedure before the appeal had been filed. Hence, the opponent had ceased to exist as a legal person before the filing of the appeal and could not file the appeal or be the appealing party in the opposition-appeal proceedings. The board stated that whether an opponent to an ongoing opposition appeal case can validly be regarded as a legal entity and act in these proceedings is a matter of national law of the state where the company is incorporated, see G 1/13 (OJ 2015, A42); in the case at issue that state was Germany. Under German law, even a company removed from the company register could validly perform procedural acts, such as filing a lawsuit in cases where a dispute is related to any form of economic interest. The board thus held that the opponent could file a valid appeal even after its removal from the company register. The appeal was filed by the representative who had acted on behalf of the opponent during the opposition. The appeal was thus admissible.