For a divisional application to be validly filed, the following requirements must be met on the date when the divisional application is filed:
An application is pending up to (but not including) the date on which the European Patent Bulletin mentions the grant of the patent (see OJ EPO 2002, 112). Where the application is refused, it is pending within the meaning of Rule 36(1) during the period for filing the notice of appeal, irrespective of whether any appeal is filed (see G 1/09). For further details of the notion of "pending" where the application is deemed to be withdrawn, see A-IV, 22.214.171.124 and sub-sections.
Where a first communication according to Art. 94(3) and Rule 71(1) and Rule 71(2) was based on the wrong application documents, notification of this communication does not start the period for voluntary division according to Rule 36(1)(a). This might happen, for example, where the applicant amended the application in response to the ESOP (see B-XI, 9 and C-II, 3.1) but the Examining Division erroneously failed to take these amendments into account when drafting the first communication. The incorrect communication will be withdrawn and a new first communication will be issued by the EPO, the notification of which starts the period under Rule 36(1)(a). The applicant will be informed of this by the EPO.
The mere deletion of subject-matter in the parent application is not prejudicial to the later filing of a divisional application. When deleting subject-matter, the applicant should, however, avoid any statements which could be interpreted as abandonment with substantive effect, thereby impeding the valid filing of a divisional application for that subject-matter (see also H-III, 2.5, last paragraph).