T 0602/24: Essential features under Rule 43(3) EPC are determined from the Applicant's perspective

In T 0602/24, the Board found that the essential features of an invention under Rule 43(3) EPC are those that the applicant considers essential for the requested patent protection, rather than those the Examining Division deems sufficient to meet substantive legal requirements. The Board interprets Rule 43(3) EPC to establish formal requirements for claims structure, not grounds for substantive rejection based on breadth of protection. 

Background

The Appellant filed an appeal against the rejection of European patent application No. 13705802.0 relating to 2K polyurethane systems with phase separation. The Examining Division rejected the main request under Art. 84 EPC, arguing that claim 1 did not contain all "essential" technical features necessary to achieve a glass transition temperature (Tg) above 60°C for the crosslinked composition. The Examining Division found that while a composition from prior art document D16 fulfilled all structural features of claim 1, it did not result in a crosslinked composition with a Tg above 60°C.

The Board's reasoning

The Board determined that the Examining Division's rejection based on missing "essential features" under Art. 84 EPC lacked legal foundation. The Board interpreted Rule 43(3) EPC  to establish formal requirements for claim structure rather than substantive grounds for rejection:

R. 43(3) EPC: Any claim stating the essential features of an invention may be followed by one or more claims concerning particular embodiments of that invention.

The Board noted that Rule 43(3) EPC defines the form and content of patent claims, and questioned why Rule 43(3) EPC should define requirements beyond form and content when all other provisions of Rule 43(3) EPC were purely formal. Since patent claims under Art. 84 EPC defined "the matter for which protection is sought" as formulated by the Applicant, the essential features would have to be those the Applicant considers essential for the requested patent protection.

The Board referenced the travaux préparatoires of EPC 1973 and EPC 2000, citing decisions T 1020/03 and G 3/14, which showed that the support requirement was considered a formal matter to ensure consistency between description and claims, not a substantive ground for rejecting overly broad claims.

Decision of the Board

The Board found the appeal admissible and overturned the Examining Division's decision. The Board determined that the invention was sufficiently disclosed under Art. 83 EPC, finding that the skilled person could achieve the required Tg based on the application's teaching. The Board also found the claimed subject matter novel but remitted the case to the Examining Division for further examination, particularly regarding inventive step. The Board emphasized that Appellants should not face rejection based on an Examining Division's assessment of what constitutes essential features for meeting patentability requirements.

Summary written by the NLO EPO Case Law Team