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  • Shubham Rana

The Federal Rules For Choosing An Expert Witness In Patent Litigation

Patent litigation in the US often involves expert witnesses playing the central role and function of a person of (ordinary) skill in the art (POSITA or PSITA). The expert witnesses assist the court with the professional or technical matters arising in a case where they testify about the complex and technical subject matter involved in the case that is litigated to provide the relevant and necessary information, and opinions as to such matters on account of their skill, technical training, or familiarity with it.

While most US judges are experienced in patent cases, they may not have the expertise in the particular technology and science involved in the case. Therefore, they are unable to draw true inferences from the facts stated by the expert witnesses and the court recognizes the opinion evidence given by the expert witnesses as admissible.

The testimony and evidence of liability and damages presented at a trial by the expert witnesses often come out to be the most important and case determinative. Even before the trial, attorneys may carefully guide an excellent expert, to secure significant success. A compelling expert report or a good claim construction may become a claim or defense determinative and may prompt a settlement discussion. Thus, identifying the elements of a case that may require expert testimony becomes a task to be done as early as possible. Parties are required to keep a contingent of experts willing to support their case.

4 Steps For Expert Witness Research

  1. The first step for the counsel is to identify the subject area(s) of expertise in their pending or existing litigation on which evidence is or may be required. Sometimes it may not be clear what are the areas of expertise involved in the case, particularly in the case of contemplated litigation. In addition, there is always a possibility of the case expanding into new issues and new subject matter areas for expert evidence. Thus, the counsel is required to be alert to the possibility of related areas of expertise to those initially identified becoming relevant. Further, the counsel also has to look at all the subspecialties within a subject area, for example, there can be numerous subspecialties within a subject area of chemistry, such as medicinal chemistry, synthetic chemistry, analytical chemistry, physical chemistry, and separation chemistry. Hence, it is often not a simple task as of just looking for a chemist expert.

  2. The second step for the counsel is to become scrupulously familiar with the subject area(s). This involves reviewing relevant literature, including leading textbooks and reviewing articles relating to the subject matter at issue. Counsel needs to be familiar with the subject matter for which expert evidence is required to critically assess whether the potential expert witness is suitable for the mandate, by considering that an expert witness has the appropriate academic or professional credentials, practical experience in the required discipline, and is of an appropriate “vintage”—that is having the right expertise and experience.

  3. The third step is to search for the appropriate candidates with expertise in the identified relevant subject area(s). Counsels in need of expert witnesses consult several sources at a time to identify potential experts. Counsels often get information about experts through the employees of the client such as inventors or in-house technicians who generally know about the leading researchers in the field. Depending on the resource and budgetary restraints of the case, other sources where the counsels usually identify potential experts are the leading academic institutions, rating agencies that provide assessments on various experts, by reviewing relevant publications and past judicial decisions that relate to the same subject matter, and recommendations from colleagues and other experts in the field. Expert consulting firms also come in useful, for identifying potential experts.

  4. The fourth step is selecting the best experts. Careful consideration of the professional and personal qualities and practical realities of an expert is required to get the best experts. Professionally, an expert must have a strong educational record with relevant experience to offer opinions that are sound, competent, and credible. They should be respected in their relevant field with a confident command of the relevant subject matter and if expected to testify, must be an effective communicator. Testifying experts, in particular, must inspire confidence, perform well under pressure, and be able to withstand rigorous cross-examination. An expert must have personal qualities such as being honest, sincere, fair, and objective. They should have a good attitude and demeanor, be likable, easy to work with, and willing to listen. They must also have sufficient time to devote to the case and should be easily accessible. Preferably, they should be sound with legal strategies and have prior experience with deposition or trial.

These steps take several weeks and significant resources, however in all cases it is important to independently test every candidate and to use your good judgment. Ultimately, the performance of an expert witness will be the reflection of the counsel’s competence and the merits of the client’s case.

The Federal Rules For The Admissibility of Expert Testimony

The admissibility of evidence is governed by Federal Rules of Evidence (FRE) both before the PTAB and the court. FRE 702 to 705 specifically concerns expert testimony. Together these rules provide, among other things, that:

1. Rule 701. Opinion Testimony By Lay Witnesses

For a witness who is not testifying as an expert, the testimony based on his opinion is limited to the one that is:

  1. “Rationally based on the witness’s perception” such that it is based on first-hand knowledge or observation.

  2. “Helpful in determining and resolving a fact in issue or to clearly understand the witness’s testimony”, such that the difficulty faced by a witness in expressing himself in language or the attempts made for choosing sides by adding meaningless assertions are ruled out.

  3. “Is not based on the scientific, technical, or other specialized knowledge within the scope of rule 702”, such that the testimony is rather based upon a layperson's knowledge.

2. Rule 702. Testimony By Expert Witnesses

  1. A person is qualified as an expert witness to offer opinion-based testimony based on his “knowledge, skill, experience, training, or education”;

  2. An expert may only testify if their “scientific, technical, or other specialized knowledge” will help the trier of the fact “understand the evidence or to determine a fact in issue”;

  3. The testimony offered by the expert must be “based on sufficient facts or data,”;

  4. The testimony offered by the expert must be “the product of reliable principles and methods,” and;

  5. “The principles and methods to the facts of the case” must have been reliably applied by the expert;

3. Rule 703. Bases Of An Expert’s Opinion Testimony

  1. The opinions presented by the experts may be based on facts or data they “personally observed,” or have been “made aware of ”. If a fact or data is of a kind that “experts in the particular field would reasonably rely on,” opinions based on those facts or data are admissible regardless of whether the underlying fact or data is itself admissible. But “if the facts or data would otherwise be inadmissible, the proponent of the opinion may disclose them to the jury only if their probative value in helping the jury evaluate the opinion substantially outweighs their prejudicial effect”;

4. Rule 704. Opinion On An Ultimate Issue

  1. An opinion offered by an expert is “not objectionable just because it embraces an ultimate issue,” for example, validity, infringement, or the measure of damages.

5. Rule 705. Disclosing The Facts Or Data Underlying An Expert’s Opinion

  1. “Unless the court orders otherwise, an expert may state an opinion — and give the reasons for it — without first testifying to the underlying facts or data. But the expert may be required to disclose those facts or data on cross-examination.”

6. Rule 706. Court-Appointed Expert Witnesses

  1. Courts are also empowered under FRE 706 to appoint their experts, but this provision has rarely been used in patent litigation.

Careful Selection of Expert Witnesses

The acceptance of opinion evidence from expert witnesses for supporting facts and data started in the late 18th century with the landmark judgment of the Folkes v. Chadd case in 1782. Then the Frye decision in 1923 came out and became the primary decision that covered the concerns regarding the admissibility of scientific evidence. The promulgation of the duties of an expert during a case started in the late 20th century with the case of Daubert. The considerations explained in this article can serve as a potential guide to assist counsel in finding and selecting the most effective expert witness.

A prepared expert is a key to the success of a case, therefore, rigorous training and preparation are required for testifying experts, to offer and defend their opinions in deposition and at trial. In turn, it serves to enhance the case because the court will be more inclined to accept the evidence offered by a carefully selected and vetted expert witness. Thus, carefully reviewing the reports or declarations and the deposition transcripts become an imperative job for the experts while being fully acquainted with the facts and data, the documents they cite, and the opinions they offer. They should also understand the legal and strategic ramifications of their statements and opinions, understand how their testimony fits in with other themes in the case, and the overall case strategy.

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The Federal Rules For Choosing An Expert
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Shubham is a research analyst at Copperpod. He has a Bachelor's degree in Electronics and Communication Engineering. His interest areas are the Internet of things (IoT), Networking, Semiconductors, Embedded System and Software.

Copperpod provides patent litigation services such as Source Code Review, Infringement Claim Charts, Document Review, and advises clients to give a clear picture of the state of the art to navigate away from the potential prior art and monetize IP assets.

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