GL E V 4 Language used in the taking of evidence

When the evidence is being taken, a party, witness or expert who is unable to express himself adequately in English, French or German or in any other official language of the contracting states is permitted to use another language. The EPO is responsible for interpreting into the language of the proceedings, assuming that this is necessary, if the evidence is taken at the request of the EPO itself.

GL E V 3 Exceptions from sections 1 and 2

Derogations from the provisions of Rule 4(1) are permitted, and these are at the discretion of the EPO. Clearly such permission must depend on the circumstances of the individual case. It may, for example, be envisaged that parties are unable to give one month's notice through no fault of their own, and, although they have made arrangements for an interpreter, the latter is unable (e.g. through illness) to attend.

GL E V 2 Language of a contracting state or other language

Any party may likewise use one of the official languages of the contracting states, other than English, French or German, on condition that they make provision for interpreting into the language of the proceedings. However, if the parties and the EPO agree, any language may be used in oral proceedings without interpreting or prior notice.[Rule 4(1); (4); ]

GL E V 1 Use of an official language

Any party to oral proceedings before the EPO may, in lieu of the language of the proceedings, use one of the other official languages of the EPO, on condition that such party either gives notice to the EPO at least one month before the date laid down for such oral proceedings or makes provision for interpreting into the language of the proceedings.

GL E V – Derogations from the language of the proceedings in oral proceedings

1. Use of an official language

2. Language of a contracting state or other language

3. Exceptions from sections 1 and 2

4. Language used in the taking of evidence

5. Language used by employees of the EPO

GL E IV 4.8 Evaluation of an inspection

In the case of a demonstration, a specific test programme under specific conditions is agreed in advance. During the demonstration itself care must be taken to ensure that the characteristics or conditions of operation claimed for the invention are complied with. Where an invention is compared under test with an item forming part of the state of the art, as far as possible the same or comparable test conditions must be applied to both.

GL E IV 4.7 Evaluation of an expert opinion

The competent department must examine whether the grounds on which an expert opinion is based are convincing. Notwithstanding its discretion in the evaluation of evidence, it may not disregard an expert opinion in the absence of grounds based on adequate specialist knowledge of its own or of another expert, irrespective of whether the latter expert is an independent expert commissioned under Rule 121 or an expert who testifies at the request of one of the parties.

GL E IV 4.6 Evaluation of the testimony of parties

Oral or written evidence given by parties or their refusal to give evidence are evaluated in the light of their special interest in the matter. Because of their special interest, the testimony of parties possibly should not be evaluated on the same level as that of neutral witnesses. This applies above all where parties have been present when witnesses have been heard and have ascertained the attitude of the competent department.

GL E IV 4.5 Evaluation of the testimony of a witness

After the witnesses have been heard, the party or parties must be given an opportunity of making observations. The observations may be made either in oral proceedings following the taking of evidence or exceptionally in writing after transmission of the minutes of the taking of evidence. The decision on this matter will rest with the competent department. The parties may file requests accordingly.

Only when this has been done may the competent department proceed to evaluate the evidence.

GL E IV 4.4 Asking for evidence

When pointing out that it cannot accept a line of argument because certain facts have not been proven, the division must do so as neutrally and objectively as possible.