PLC has recently picked up a 2012 EPO Board of Appeal decision that considers exceptions to the legal principle of the prohibition of reformatio in peius in relation to patent claims. Reformatio in peius is the principle, explained in greater detail here, that a decision may not be reached which would put an appellant in a worse position than it was in under the impugned decision) meant that the amendment should not be allowed.
Case T 1843/09 Biaxially oriented film/TORAY INDUSTRIES, INC, 6 June 2012, the Board of Appeal held that the earlier decision of the Enlarged Board of Appeal G 1/99, which provided three precisely defined exceptions to the principle, was not limited to the factual situation underlying that decision, in which it was necessary to revoke a patent as a direct consequence of an inadmissible amendment allowed by the Opposition Division in its interlocutory decision. In this case, the factual situation had changed as the result of the late admission into the proceedings of a prior art document. The Enlarged Board in G 1/99 had made it clear that exceptions to the principle of reformatio in peius were to be allowed as a matter of equity in order to protect a non-appealing proprietor against procedural discrimination in circumstances where the application of that principle would impair the legitimate defence of its patent. This was the situation here, which was unusual in that the deletion of the critical priority-destroying feature was exceptionally justifiable while also respecting the rule that such an exception should only be construed narrowly.