Filing European Divisional Applications

A divisional application is an application that has been divided from an earlier (“parent”) application. The earlier parent application may itself be a divisional application. A divisional application takes the same filing date as the parent application. Therefore, the divisional application will have a maximum patent term expiring at the same time as the parent application, i.e. 20 years from the filing date (provided renewal fees are paid).

Why file a divisional application?

Divisional applications may be filed for various reasons. For example:

  1. The claims of the parent application were considered by the EPO Search or Examining Division to lack unity (i.e. relates to more than one invention). The applicant may choose to argue against a lack of unity objection. However, if the argument is unsuccessful, the additional invention(s) can only be pursued by filing one or more divisional applications.
  2. The applicant wishes to have a “back-up” application in case of refusal of the parent application.
  3. The applicant wishes to have a “back-up” application in view of potential opposition proceedings against the parent application.
  4. The applicant wishes to pursue claims to subject-matter that has not been searched by the EPO, for example because of a lack of unity as above, or because the subject-matter was present only in the description of the parent application as filed, but not present in the claims.

Filing a divisional application

Only the registered applicant(s) of the parent application can file a divisional application, although once filed, the divisional application can be assigned to another party independently of its parent application. The divisional application can only include designations for contracting and extension states that were validly designated in the parent application.

Once filed, the divisional application is treated as a separate, new application, and will be searched, published and examined independently of its parent application. Thus, a divisional application, once granted, can be subject to EPO opposition, national validity or infringement proceedings independently of its parent.

Subject-matter of the European divisional application

A divisional application can only include subject-matter that was originally disclosed in the parent application from which the divisional application is derived. In the case of a parent application (P) from which a first divisional application (D1) has been filed, D1 can only contain subject-matter that was present in P. If a second divisional application (D2) is to be filed based on D1, D2 can only include subject-matter disclosed in D1. D2 cannot include subject-matter disclosed in P that is not present in D1.

The test for whether the subject-matter of a divisional application was actually disclosed in its parent application is treated very strictly by the EPO - the subject-matter must be “directly and unambiguously derivable” from the parent application. Otherwise, it extends beyond the content of the parent application and it must be deleted from the divisional application.

Furthermore, a parent and divisional application should not claim the same subject-matter in order to avoid an objection of double patenting.

When can a European divisional application be filed?

A European divisional application can only be based on a pending European application. For an earlier application which is a PCT application designating Europe, the application can only be divided once the PCT application has entered the European regional phase. A European application is considered to be pending up until the day before the date of grant or before the date of the decision to refuse.

From 1 April 2010, a divisional application can only be filed on a pending application and:

(a) before expiry of 24 months from the Examining Division’s first communication (typically a first examination report or a notice of intention to grant) in respect of the earliest application for which a communication has been issued [“voluntary divisional” – such as for examples 2-4 above], or

(b) before expiry of 24 months from any communication in which the Examining Division has raised a specific objection of lack of unity for the first time [“mandatory divisional” – example 1 above].

Transitional provisions for pending European patent applications provide that if the new voluntary or mandatory divisional time limits have expired before 1 April 2010, or if they are still running on 1 April 2010, divisional applications can still be filed until the deadline of 1 October 2010.

The time limits under the new rules and the transitional provisions cannot be extended, and are excluded from the EPO’s further processing provisions (although "Re-establishment of Rights" is available).

The interpretation of these new time limits has not been fully clarified – for example:

Until legal certainty regarding the wording of these rules can be assured, a safe approach would be to calculate the voluntary divisional filing time limit (a) based on the first communication from the Examining Division that issued on any application in the European family (whether or not this is an examination report or notification of intention to grant). For mandatory divisionals, a safe approach to divisional strategy planning would be to take the time limit (b) as applying strictly to the subject-matter that caused the lack of unity objection.

Further, since the time limit (a) for filing voluntary divisional applications applies to all applications, whereas the time limit (b) for filing mandatory divisional applications only applies if the Examining Division raises a new objection of lack of unity, it would be wise to consider time limit (a) as the deadline date when planning divisional filing strategy, i.e. applicants should not routinely rely on time limit (b).