The procedure defined in the EPC for the filing of divisional applications is self-contained and complete (see e.g. T 587/98, OJ 2000, 497). The procedure concerning the divisional application is, in principle, independent from the procedure concerning the parent application. Although there are some connections between the two procedures (e.g. concerning time limits), actions (or omissions) occurring in the procedure concerning the parent application after the filing of the divisional application should not influence the procedure concerning the latter (G 4/98, OJ 2001, 131). The parent application also does not have any procedural priority over the divisional application, which is like any other application and in particular does not have subordinate procedural status (T 1177/00, T 1176/00).

The consequence of the procedural independence of the divisional application can be seen in T 1254/06. In this case, the examining division had refused the divisional application and the applicant did not appeal. In the appeal proceedings concerning the parent application (in which the applicant had made the same requests as in the proceedings concerning the divisional application) the question arose whether the legal force of a refusal decision in respect of the divisional application also affected the parent application procedure to the extent that it could prevent the EPO (including the boards of appeal) from dealing with the substance of identical requests. The board stated that the principle that both proceedings were independent meant that a refusal decision in one procedure did not have a preclusive effect with respect to identical requests in the other procedure. This applied in particular when, as in this case, the refusal decision was made not by the board of appeal but by the examining division, because the first-instance administrative decision did not have true res judicata effect.

In case J 5/07 the appellant had failed to file observations according to Art. 96(2) EPC 1973 (Art. 94(3) EPC). The appellant's request for further processing was rejected on the ground that the omitted act was not completed in due time (Art. 121(2) EPC 1973; R. 135(1) EPC). The appellant filed an appeal against this decision, arguing that the omitted act was in fact completed because in response to the communication a divisional application was filed by the appellant. The Legal Board held that, as a consequence of the principle that a divisional application was legally and administratively separate and independent from the grant proceedings concerning the parent application, the filing of a divisional application could not constitute a response to the invitation by the examining division in the parent application within the meaning of Art. 96(3) EPC 1973 (now Art. 94(4) EPC). There was no logical or legal basis for treating an act during the grant procedure for one application (the divisional) as the procedural step required to make up for a failure to comply with a time limit to be observed in entirely separate grant proceedings (the parent).

The board in T 591/05 could not see how the filing and the status of a divisional application might have had any bearing on the admissibility of the appeal against the parent. In particular, any allegation relating to the circumstances under which the divisional application had been filed (here: appellant had expressed the intention to file a divisional application) might have been pertinent to the legal status of the divisional application, but was irrelevant to the issue of the admissibility of the appeal.

In T 1705/11 the board held that facts, evidence and requests or submissions made or filed in the parent procedure were not automatically part of the divisional procedure. A general citation or a mere reference to facts and/or evidence, such as to prior art documents, filed in the parent procedure but not physically filed or incorporated into the divisional application procedure did not constitute a reservoir upon which a party might draw at its convenience and at any time in the divisional application procedure.