An International Guide to
Patent Case Management for Judges

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3.6.5 Evidence Expert evidence

A major challenge to be faced by cases involving patent law is the production of expert evidence because, as a rule, they are complex and require professionals with specialized knowledge. It is necessary to note that, although expert evidence is important – because it is a technical opinion that contributes to the assessment of a potential infringement of patent law – it does not bind the judge. This is because the principle in Brazilian law is that a judge has exclusive jurisdiction to apply the law after examining the facts alleged and the evidence produced.

As a rule, the expert is appointed by the judge (Article 465 of the CPC). Nevertheless, it is possible for parties to present, by mutual agreement, another expert they wish to analyze the case. In addition to the official expert, parties are entitled to appoint technical assistants, who will be allowed to follow up on the steps taken by the expert. In case of a complex expert analysis that covers more than one area of specialized knowledge, the judge may appoint more than one expert, and the party may appoint more than one technical assistant (Article 475 of the CPC). Experts must be registered with each court’s system.

Expert evidence comprises an examination, inspection or evaluation but is rejected by the judge if the evidence of the fact does not depend on the special knowledge of a technician, if it is unnecessary in view of other evidence produced, or if verification of the evidence is impossible.

The expert must ensure that the technical assistants of the parties have access to and follow up on the measures and examinations that the expert carries out, provided that the assistants are previously notified of the acts. The parties will be notified of the date and place designated by the judge or indicated by the expert to start the production of evidence.

The expert may be replaced if they lack technical or scientific knowledge or if, for no legitimate reason, they fail to comply with the assignment within the term they were granted. The expert and the technical assistants must deliver the report and opinions, respectively, within a period set by the judge.

After the expert is appointed, the parties must present their questions to the expert. These items are answered by the expert together with the disputed points established by the judge in the pre-trial order. This is the moment when the party must go deep in attributing the technical details about the kind of patent infringement.

Parties may also, within 15 days from the notice of the order appointing the expert, argue for the refusal of the expert due to a conflict of interest or disqualification and submit questions. They may present additional questions during the measure, which may be answered by the expert in advance or at the trial hearing. The judge has a duty to dismiss impertinent questions and put forward questions that the judge deems necessary to clarify the case (Article 470 of the CPC).

There is no legal limitation to the number of questions; however, the opposing party may object to questions that are not covered by the disputed points established in the pre-trial order or that go beyond the limits of the expert evidence also defined by the judge. Since the judge may divide the production of evidence, it is possible for questions related to the part postponed to a subsequent examination to be rejected, without prejudice to resubmission, if a new expert examination is granted on that part of the evidence.

The expert is prohibited from exceeding the limits of their designation and from issuing personal opinions that exceed the technical or scientific examination of the subject matter of the expert analysis. Their report must contain the following:

I – the exposition of the subject matter of the expert analysis;

II – the technical or scientific analysis carried out by the expert;

III– the indication of the method used, clarifying it and demonstrating that it is predominantly accepted by specialists in the field of knowledge from which it originated; [and]

IV– the conclusive answer to all the questions presented by the judge, the parties, and the Public Prosecutor’s Office. (Article 473 of the CPC)

The expert must file a report in court within the term set by the judge and at least 20 days before the trial hearing. The parties can be summoned, if they wish, to express their opinion on the expert’s report within a common term of 15 days, provided that the technical assistant of each party may, within the same term, present their respective opinions.

The expert of the court has the duty to clarify, within 15 days, any point on which there is disagreement or doubt by either party, by the judge, by the Public Prosecutor’s Office or in the opinion of the technical assistant of a party. If further clarification is still necessary, a party can request the judge to summon the expert or technical assistant to attend the trial hearing, making, at that moment, the questions in the form of requirements. If a matter is not sufficiently clarified, the judge will determine, at their own initiative or at the request of a party, the carrying out of new expert analysis.

Finally, the Brazilian system also admits a simplified model of technical evidence consisting of the presentation of an expert opinion. In this kind of evidence, the expert does not focus on a specific factual dispute. Instead, the purpose is only to solve technical doubts – based on the state of the art and on specialized literature – that will help the judge understand and decide the case. As it is a simplified model, it can be used only in specific cases, at the judge’s discretion, enabling cost reduction. Testimonial evidence

The convenience of producing testimonial evidence is analyzed by the judge at the moment of the pre-trial order, assigning procedural burdens. As a rule, it is incumbent upon the parties to request the production of testimonial evidence and justify its need. It is possible, however, that even without a request by the parties, the judge determines at their own initiative that it is necessary to carry it out.

A list of witnesses is to be presented at least prior to the trial hearing. Procedural legislation provides for limits on the maximum number of witnesses allowed (Articles 357 (6)–(7), 450–463 of the CPC).

Questions are asked by the parties directly to the witness, starting with the party that called the witness. The judge will disallow questions that may induce the answer, that are not related to the matters of fact of the subject matter of the evidentiary stage, or that imply a repetition of another question already answered (Article 459 of the CPC). The judge may question the witness either before or after the inquiry made by the parties (Article 459(1) of the CPC).