An International Guide to
Patent Case Management for Judges

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2.6.7 Evidence

Patent litigation proceedings are typically commenced by a patentee alleging infringement, with the respondent denying infringement and cross-claiming for revocation of the patent. The court typically hears and determines infringement and invalidity simultaneously.

Once initial procedural steps, including the filing of pleadings, are completed, each party prepares evidence in accordance with a timetable set by the court. Evidence in patent cases is usually provided in the form of written and verified affidavits. Documents can be annexed or exhibited to affidavits, which are then tendered in court and admitted as evidence. Prior to trial, there will usually be one or more case management conferences and procedural steps to identify which affidavit evidence will be relied on at trial. Each party also notifies which of the opposing parties’ witnesses it will call for cross-examination.

At the trial, any affidavit evidence upon which a party intends to rely will be formally “read” by the party relying on it and admitted into evidence. A person that has given evidence in affidavit form may be required to appear for oral cross-examination by the opposing party. Cross-examination of the witness is not confined solely to matters in the witness’s affidavit: any issue relevant to the proceedings can be canvased. After cross-examination is completed, the party calling the witness has the right to reexamine the witness in relation to matters arising out of cross-examination. Expert evidence

Issues of patent construction and, consequently, infringement and validity are considered through the lens of a notional addressee of the patent specification – a person skilled in the art. The background and experience of the person skilled in the art will differ depending on the subject matter of the specification. Of course, ultimately, these issues are determined by the court. While the Federal Court judges who hear patent cases are generally highly experienced and often former patent counsel themselves, they do not always have technical qualifications. Consequently, in almost all patent cases, independent expert evidence is called to assist the court in placing itself in the position of the person skilled in the art.

While the Federal Court of Australia can appoint its own expert or assessor (technical assistant), these powers are rarely used, and, in the majority of cases, competing experts are engaged by the parties themselves. The purpose of expert evidence is for the court to receive the benefit of the objective and impartial assessment of an issue using the specialized knowledge of the expert.96

Where an expert witness is retained for the purpose of preparing a report or giving evidence as to an opinion held by the expert based on their specialized knowledge, the expert is provided with the Federal Court’s Expert Evidence Practice Note (GPN-EXPT) and all relevant information so as to enable the expert to prepare an independent report. The expert’s ultimate obligation is to assist the court rather than act as an advocate for a party. The parties and their legal representatives have obligations to maintain the independence of the expert witness and must not pressure or influence the expert into conforming their views with the parties’ interests.

Expert evidence can assist the court on a number of issues arising in a patent case. Importantly, in relation to patent construction, expert evidence can assist the court in understanding the context of a patent and the meaning of any technical terms or “terms of art.”97 On infringement, expert evidence can assist the court in understanding the functionality and features of an alleged infringing product or process and how it may map to the patent claims in issue. In relation to validity, expert evidence can assist the court in understanding the extent and nature of disclosures in the prior art to assist in a novelty assessment. Further, expert evidence is often relied on to establish the state of the CGK in the relevant field before the priority date. This is an important step in assessing whether the claimed invention would have been “obvious” to a person skilled in the art.

The court will hear and assess the evidence from the competing persons skilled in the art called by the parties, but, ultimately, all these issues are for determination by the court. Position statements, product descriptions and “primers”

In appropriate cases, the party alleging patent infringement may be required to provide a position statement on infringement. This is a document that supplements an infringement pleading and provides more detail on how the patentee alleges the impugned product takes the features of the patent claims. It concisely states the facts and matters relied upon in support of the infringement allegation, including reference to the integers of any claim alleged to have been infringed. While it does not constitute evidence in the case, it will often be prepared with input from an expert.

The respondent is often required to provide a position statement on (non)infringement in response. In some cases, the respondent may also be required to provide a product description. This is a detailed description of the product or process alleged to be infringed. This procedure has been developed in an attempt to avoid time-consuming and costly discovery or experimental procedures for establishing the form and functionality of the alleged infringement. The product description is generally verified by an officer of the respondent with knowledge of the product.

In an appropriate case, the court may require the parties to produce an agreed primer. This identifies the agreed technical background to the invention claimed in the patent. The primer typically includes an agreed description of the CGK at the priority date. In an appropriate case, the primer may be accompanied by an agreed glossary of key terms. The primer provides a starting point for the court in addressing the state of the art, particularly in relation to validity. Conference of experts and joint report

Where multiple experts are retained to provide evidence to the court, the court increasingly requires that experts meet in a conference ahead of the trial to attempt to narrow the issues between them. There is often a lot of background information in the experts’ affidavit evidence in relation to the technology in issue and the CGK that is not controversial. The parties and their legal representatives do not participate in the expert conference, but, often, a court officer such as a registrar will be called on to facilitate.

At the conclusion of the conference, the experts prepare a joint report, which identifies the issues in respect of which they agree or disagree. The joint report typically contains a succinct explanation for any differences of opinion. This procedure enables the court and the parties to focus on the issues that are genuinely in dispute at the trial. Concurrent evidence

In most patent cases, the Federal Court of Australia has adopted the practice of concurrent expert evidence (also colloquially known as “hot-tubbing”). At the trial, after being sworn in, the experts engaged by each party are questioned together. Prior to a hearing at which concurrent expert evidence is to be given, the parties and their legal representatives confer and consider an agenda, an order and manner in which questions are to be asked, and whether cross-examination will take place during concurrent with evidence, or after its conclusion.

Concurrent expert evidence typically involves the following process:

  1. 1. The parties’ experts prepare a joint report, identifying their areas of agreement and disagreement.
  2. 2. The experts are called into the witness box together.
  3. 3. Each expert takes turns in giving evidence.
  4. 4. An expert can comment on another expert’s evidence.
  5. 5. The parties’ representatives cross-examine the experts, with each expert being able to give evidence and comment on another expert’s evidence.

This practice allows an expert to consider and comment on another expert’s opinion in real time and allows the court and the parties to focus on the real issues in dispute. The objective is to facilitate an environment whereby the experts, the parties and the court can engage in a dialogue that enables a thorough and frank examination of the issues. Expert evidence in infringement proceedings

Expert evidence relating to infringement claims is prepared and presented in a similar fashion to invalidity evidence.

The infringement issues on which expert evidence is commonly received include:

  • technical matters bearing on the proper construction of the specification and claims;
  • evaluation of whether a product or process possesses the integers of relevant claims (e.g., by an engineer, clinician, industry expert or patent attorney);
  • matters of industry knowledge relevant to infringement (e.g., the uses to which a particular product may be put or the characteristics of a market in which the product is supplied); and
  • calculations bearing on the quantum of relief to which an applicant may be entitled on an account of profits or by way of compensatory damages.

Although infringement issues may, to an extent, be separated from invalidity issues in joint report and concurrent evidence processes, there is a significant degree of overlap between the issues (particularly in relation to construction and CGK) such that a party will often have one or more experts giving evidence on infringement and invalidity issues in the proceeding.