The Enlarged Board of Appeal ("EBA") of the European Patent Office ("EPO") has confirmed that European divisional patent applications are to be treated in the main as ordinary European patent applications.

In applying this principle, the EBA held that:

the inclusion of new subject matter on filing a divisional application is not an irrecoverable defect – such subject matter may be removed subsequent to filing (irrespective of whether the parent application is still pending); and

"cascading" divisional applications are permissible, provided that the subject matter of the divisional(s) is disclosed in each of the preceding applications.


A divisional patent application is an application that contains matter from a previously filed "parent" application. Although subsequently filed, a divisional application may retain the filing date and priority date of the parent application, provided its subject matter does not extend beyond the content of the parent application. It is also possible to have a divisional from an application that is itself a divisional – this can give rise to a number of divisional applications "cascading" from the original divisional application.

Divisionals were originally conceived to overcome "lack of unity" objections i.e. where a patent application relates to more than one invention. Divisionals are now, however, sophisticated weapons in a patentee's armoury. For example, subject matter of doubtful validity can be isolated from a pending patent application by dividing it out into a divisional application. Divisional applications may also be kept pending years after the grant (or refusal of grant) of the original application. Whilst pending, the patentees have been known to fine-tune the claims of a divisional (without adding matter) to increase the probability of catching competing products or processes.

Such practices have lead to concerns expressed by the Technical Board of Appeal ("TBA") that divisionals (especially a cascade of divisionals) "…might potentially contravene the generally acknowledged principle that the examining procedure at the EPO must be conducted in such a way as to ensure that, within a reasonable period of time after filing of a patent application, the public should have a fair knowledge of the extent of the exclusive rights sought by the applicant".1

As a result, the TBA started taking an increasingly strict approach to granting divisionals. The question of the correctness of such practices was referred in a number of cases to the EBA, which heard the references together.2 Pending the decision, the EPO suspended the examination or opposition proceedings concerning any divisional applications found to contain added subject matter. The decision of the EBA was published on 28 June 2007.3

Decision of the EBA

Issue 1: Can a divisional application be amended after filing to remove added matter

Article 76(1) EPC requires that a divisional application "may be filed only in respect of subject matter which does not extend beyond the content of the earlier application as filed; in so far as this provision is complied with, the divisional application shall be deemed to have been filed on the date of filing of the earlier application and shall have the benefit of any right to priority".

The EBA was asked whether a divisional application which does not meet the requirements of Article 76(1) EPC because, at its actual filing date, it extends beyond the content of its parent application, could be amended later to make it a valid divisional application.

The EBA answered this question in the affirmative. In reaching this decision, it stated that a divisional application is a new application which is separate and independent from the parent application and that: 

"divisional applications are to be treated in the same manner as ordinary applications and subject to the same requirements, unless specific provisions of the EPC, in particular those of Article 76 or Rule 25 EPC, require something different". 4

The EBA stated that it is an important principle under the EPC that applicants have the opportunity to amend their applications to overcome any objections raised by the Examining Division of the EPO. Article 123(2) EPC enables applicants to amend an application to remove any added matter and, as there is no specific provision to the contrary, the EBA held that this principle also applies to divisional applications.

Issue 2: Can such amendment take place when the parent application is no longer pending?

Rule 25(1) of the Implementing Regulations to the EPC provides that "the applicant may file a divisional application relating to any pending earlier European patent application". Accordingly, a divisional application cannot be filed after the parent application has been refused or withdrawn, or deemed withdrawn, and cannot be filed after grant of a patent on the parent application.

The EBA was asked, if the divisional application can be amended after filing to remove added matter, whether such amendments are still possible when the earlier application is no longer pending.

The EBA held that such amendments were allowable irrespective of whether the earlier application is still pending. It cited with approval the EBA's view in Opinion G 4/98, that, although there are some connections between the procedures concerning the divisional application and its parent application (e.g. concerning time limits), actions occurring in the procedure concerning the parent application after filing of the divisional application should not influence the procedure of the divisional application. 5

Issue 3: Are there any further limitations on the right to amend a divisional application?

The EBA was also asked whether there are any further limitations on the right to amend a divisional application after filing, beyond those imposed by Articles 76(1) and 123(2) EPC.

The EBA held that amendments to divisional applications are allowed under Article 123(2) EPC to the same extent as amendments to any other non-divisional applications.

Issue 4: Are there any additional requirements in respect of cascading divisional applications?

In cases of cascading divisional applications, the TBA had held that "the content of the earlier application" in Article 76(1) EPC was delimited by the claims of the parent application and that, therefore, the subject matter of a divisional of a divisional could not go beyond the claimed subject matter of the previous divisional. This issue was also referred to the EBA.

The EBA held that Article 76(1) applies to cascading divisionals, and that, therefore, a divisional application (of whatever generation) can be the "earlier application" of Article 76(1) EPC for the purposes of a further divisional application. Further, it stated that the EPC does not contain any additional restrictions relating to the admissibility of cascading divisional applications (such as a requirement that the subject matter of the claims of each divisional should be nestled within the subject matter of the claims of its divisional predecessor).


The EBA's decision will be welcomed by research-based entities, especially those whose divisional applications have been held in limbo over the past few years. The EBA has acknowledged the concern that divisional applications may be used by applicants to postpone the date on which the extent of their exclusive rights is defined. The EBA, however, is reluctant to address this issue by introducing arbitrary restrictions on the grant of divisionals contrary to the wording of the EPC.

As stated by the EBA:

"The Board finds it unsatisfactory that sequences of divisional applications each containing the same broad disclosures of the original patent application, by means of at least an unamended description, should be pending for up to twenty years. If administrative measures, such as giving priority to the examination of divisional applications and bundling and speedily deciding co-pending divisional applications so as to minimize the possibility for applicants to keep alive subject-matter on which the Examining Division had already given a negative opinion in one application by means of refiling the same subject-matter again and again, are not adequate, it would be for the legislator to consider when there are abuses and what the remedy could be".6