Double patenting – referral to the Enlarged Board of Appeal

T 0318/14 concerns an appeal based on an Examining Division’s decision to reject EP 2429542 on the basis of double patenting.  EP ‘542 has identical claims to, and claims priority from, granted patent EP 2251021. The Board of Appeal in T 0318/14 affirmed that while there is no statutory basis for a double patenting rejection under the European Patent Convention, that Enlarged Board of Appeal decisions G 1/05 and G 1/06 set out the principles for such a rejection on the basis that an applicant has “no legitimate interest in proceedings leading to the grant of a second patent for the same subject-matter if he already possesses one granted patent therefor”. 

Moreover, while G 1/05 and G 1/06 related to divisional applications claiming the same subject-matter, the Board considered that the principles should not be restricted to such situations. Thus, an interesting question arising in T 0318/14 is: ‘does an additional 12 months of patent term enjoyed by applicant for EP ‘542 versus EP ‘021 constitute a “legitimate interest”?’ Indeed, in decision T 1423/07, the Board held that a legitimate interest did exist in a scenario where there were different applicants for the priority document and later European application claiming the same subject-matter. 

Nevertheless, the case law in this area is divergent, thus a referral to the Enlarged Board of Appeal was considered appropriate. The questions referred seek to establish:

  • whether a European patent application can be refused if it claims the same subject-matter as a European patent granted to the same applicant, which does not form part of the state of the art;
  • if so, the conditions for such a refusal and whether these differ for: applications filed on the same date; divisional applications; or applications and their priority filings; and
  • whether, in the latter case, the additional 12 months of patent term constitutes a “legitimate interest”.

Needless to say, having answers to each of the referred questions will improve legal certainty in this somewhat grey area of European patent law.

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David Hobson
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