Complaints confidentiality during opposition proceedings

The procedures regarding the disclosure of communications during opposition proceedings before the European Patent Office (EPO) have been clarified by a recent case heard by the Technical Board of Appeal.

Under Rules 79(1) and (2) EPC, the EPO should communicate any notices of opposition to the patent proprietor and any other opponents. The proprietor is to be given a period of time to respond and to file any amendments, which the EPO should also communicate to the other parties. Under Rule 79(3) EPC, the EPO should communicate any observations and amendments filed by the patent proprietor to all parties and again invite them to reply within a specified period. In practice, the formalities officer communicates observations filed by any of the parties to all of the other parties.

However, in recent case T 1691/15, it arose that an opponent had filed a complaint to the Directorate Quality Support (DQS) which had resulted in a series of exchanges (including emails, letters and a telephone communication) between the EPO and the opponent, and that the EPO had failed to communicate these exchanges to the patent proprietor. The DQS is the department of the EPO which handles all complaints and generally stores all correspondence on a private part of a case file which does not become publicly accessible.

In T 1691/15, the particular complaints which had been filed had a bearing on the ongoing opposition proceedings. The Board of Appeal decided that such exchanges stored on the private part of the file, and which have a substantive or procedural bearing on the issues at hand, should in fact be communicated without delay to all parties to the opposition proceedings in compliance with Rule 79 EPC. Furthermore, the Board stated that exchanges of such significance should, by definition, appear in the public part of the file. In this case, the Board provided the proprietor with additional time to review the private exchanges in order to prepare counterarguments.

The Board of Appeal also noted that the Opposition Division of the EPO does not regularly check the entire file of a case, nor does it normally consider whether there are non-public parts of the file which should be made public or at least disclosed to the parties to proceedings.