A divisional application can also be an earlier application in the sense of Art. 76(1) for the purposes of one or more further divisional applications. The characterising feature of a sequence of divisional applications each divided out from its predecessor is that each member of the sequence claims as date of filing the date of the root application in which the subject-matter divided out in sequences of divisional applications was first disclosed (see G 1/05, G 1/06).
In a sequence of divisional applications, a first-generation divisional application is a divisional application based on an application which is not itself a divisional application, i.e. the root application. A second-generation divisional application is a divisional application based on a first-generation divisional application; and so on.
Source: http://www.epo.org/law-practice/legal-texts/html/guidelines/e/a_iv_1_1_2.htm
Date retrieved: 17 May 2021