In addition to the Boards of Appeal, the European Patent Office includes an Enlarged Board of Appeal. This board does not constitute an additional level of jurisdiction in the classical sense. This instance takes decisions only when the case law of the Boards of Appeal becomes inconsistent or when an important point of law arises. Its purpose is "to ensure uniform application of the law" and to clarify or interpret important points of law in relation to the European Patent Convention. Only the Boards of Appeal themselves and the President of the EPO can refer a question to the Enlarged Board of Appeal. In the first case, the Enlarged Board issues a decision, while in the latter case it issues an opinion. Petitions for review of decisions of the Boards of Appeal are also examined by the Enlarged Board of Appeal.
After examining the allowability of an appeal, a Board has the discretion to either "exercise any power within the competence of the department which was responsible for the decision appealed" (correction of a decision) or "remit the case to that department for further prosecution" (cassation of a decision). When a board remits a case to the first instance, it does so notably to give the parties the possibility of defending their case as to the substance in front of two instances.
Parties with a legitimate interest may request accelerated processing of the appeal proceedings. Courts and competent authorities of the contracting states may also request accelerated processing. Exceptionally the Board of Appeal may itself decide to accelerate the proceedings, ex officio, "for example in view of the disadvantages which could ensue from the suspensive effect of the appeal in the case in question".
During an appeal, oral proceedings may take place at the request of the EPO or at the request of any party to the proceedings, i.e. the applicant (who is, in pre-grant appeal, the appellant), or the patentee or an opponent (who are, in opposition appeal, appellant or respondent). The oral proceedings in appeal are held in Munich, and are public unless very particular circumstances apply. This contrasts with oral proceedings held before an Examining Division, which are not public. The list of public oral proceedings in appeal before the EPO is available on its web site. The right to oral proceedings is a specific and codified part of the procedural right to be heard. A decision is often taken at the end of the oral proceedings.
The legal system established under the EPC differs from a common law legal system in that "[it] does not treat (...) established jurisprudence as binding." Under the EPC, there is no principle of binding case law. That is, the binding effect of board of appeal decisions is extremely limited. A decision of a Board of Appeal is only binding on to the department whose decision was appealed, insofar as the facts are the same (if the case is remitted to the first instance of course). However, "[if] the decision which was appealed emanated from the Receiving Section, the Examining Division shall similarly be bound by the ratio decidendi of the Board of Appeal."
A decision of the Enlarged Board of Appeal (pursuant to ) is only binding on the Board of Appeal in respect of the appeal in question, i.e. on the Board of Appeal which referred the question to the Enlarged Board of Appeal. In practice however, the Boards of Appeal rarely diverge from the case law established by the Enlarged Board of Appeal.
If "a Board [of Appeal] considers it necessary to deviate from an interpretation or explanation of the [EPC] given in an earlier decision of any Board [of Appeal], the grounds for this deviation shall be given, unless such grounds are in accordance with an earlier opinion or decision of the Enlarged Board of Appeal. The President of the European Patent Office shall be informed of the Board's decision."
Members of the Boards are only bound by the European Patent Convention. They are not bound by any instructions, such as the "Guidelines for Examination in the European Patent Office". They have a duty of independence.
However, since "the [appeal] boards' administrative and organisational attachment to the EPO which is an administrative authority obscures their judicial nature and is not fully commensurate with their function as a judicial body" , there have been calls for creating, within the European Patent Organisation, a third judicial body alongside the Administrative Council and the European Patent Office. This third judicial body would replace the present Boards of Appeal and could be called the "Court of Appeals of the European Patent Organisation" or the "European Court of Patent Appeals". This third body would have his own budget, would have its seat in Munich, Germany and would be supervised "without prejudice to its judicial independence" by the Administrative Council of the EPO. The EPO has also proposed that the members of the Boards of Appeal should be appointed for lifetime, "with grounds for termination exhaustively regulated in the EPC". These change would however need to be approved by a new Diplomatic Conference.
The number before the oblique is the serial number, allocated by chronological order of receipt at the DG3, the Directorate General 3 (Appeals) of the European Patent Office. The last two digits give the year of receipt of the appeal in DG3. The letter "L" does not refer to a decision of a Board of Appeal but to a Legal Advice of the EPO, while the letter "V" refers to a decision of an Examination or Opposition Division.
In addition to their alphanumeric reference, decisions are sometimes referred to and identified by their date. This enables to distinguish between decisions bearing the same alphanumeric reference but issued at a different date (e.g. T 843/91 of March 17, 1993 and T 843/91 of August 5, 1993 , T 59/87 of April 26, 1988 and T 59/87 of August 14, 1990 or T 261/88 of March 28, 1991 and T 261/88 of February 16, 1993 ). These cases are relatively rare however.