An appeal can be filed against decisions of the departments of first instance of the European Patent Office (EPO). The appeal is filed with the EPO's boards of appeal in a judicial procedure in which a board acts as the department of final instance in grant, opposition, limitation and revocation procedures before the EPO.
An appeal must be filed in writing (including fax or online filing with EPO software) within two months of notification of the contested decision. It is not valid unless the appeal fee has been paid (see the current "Schedule of fees and expenses"). Then, within four months from the date of notification of the decision, a written statement must be filed that sets out the grounds of appeal. The above time limits are not extendable.
The board of appeal examines whether the appeal is admissible, and, if it is, whether it is allowable. It then rules as to whether it will correct the decision or remit the case to the relevant department for further prosecution.
Oral proceedings may be held at the request of the EPO or any party to the appeal, i.e. applicant, patentee or opponent. They are held in Munich and are public, unless otherwise specified. A decision is often taken at the end of the proceedings.