HGF Presents
Overview of Oppositions & Appeals at the EPO
September 2025
Video overview:
Opposition at the EPO must be filed within 9 months of grant before the Opposition Division (OD). It typically takes around 20 months to reach a decision, which can be appealed to the Technical Board of Appeal (TBA).
Appeals are heard by a 3-member TBA panel (sometimes expanded to 5), with a deadline of 2 months from the OD decision to file notice of appeal, and a further 2 months to file the complete grounds of appeal. Appeal proceedings typically take 2–3 years and are final, with no further appeal possible. The TBA may refer certain issues to the Enlarged Board of Appeal (EBA) to assist it in reaching a decision, but the EBA is not a further forum for appeal.
The EPO emphasizes written proceedings and early submission of all arguments and evidence. Oral proceedings serve as the final stage of the process and a decision is typically announced at the hearing. The process is designed to be cost-effective, with strict procedural rules.
Grounds for opposition include:
Added matter
Lack of sufficiency
Excluded subject matter
Lack of novelty
Lack of inventive step
Clarity and double-patenting are not valid grounds.