Choosing the Right Expert Can Make All the Difference

By Aaron Stiefel

In virtually every patent litigation, a key task for the trial lawyer is identifying, recruiting and retaining expert witnesses.

Counsel for the alleged infringer may well retain one or more experts to explain that the accused product or method does not infringe, that the patent-in-suit was anticipated by or obvious in view of the prior art, that the patent claims failed to satisfy the written description or enablement requirements of 11 U.S.C. Section 112 and that damages, if any, should be minimal.

The patent owner may likewise use experts to testify regarding infringement, validity and damages in support of the testimony of one or more inventors.

While there is undoubtedly value in using an expert who holds a prestigious academic position and can boast of a slew of awards, speaking engagements and publications, your best choice may not be the expert with the most impressive curriculum vitae.

Discussed below are some of the considerations that should bear on your choice of an expert. First and foremost you should focus on the expert’s skill at communicating with the fact-finder. A wealth of technical knowledge and a glittering resume will not mean much if the expert is unable to translate his or her expertise into cogent testimony.

Moreover, in patent cases, the ability to communicate effectively means more than just having a command of the language. The expert will be required not only to render an opinion, but also to explain very complex material and to transmit highly technical concepts in layman’s terms.

Frequently, the parties will use experts to provide the court with a tutorial in advance of, or as part of, a Markman hearing. Thus, you want the expert to be a capable teacher.

For the accused infringer, the expert’s ability to communicate and connect with the judge or jury is often vital. The patentee likely has the benefit of telling its story through an inventor whose proudest professional accomplishment is on the line. The inventor is thus a motivated witness with a story to tell, who knows the subject matter thoroughly and may be held in high regard, particularly by a jury, by virtue of his or her invention.

The accused infringer’s expert, by contrast, has no personal stake in the case and no personal story to relate. Yet, the expert may have to serve as the principal voice of the accused infringer. Accordingly, it is essential that the accused infringer find an expert that cannot only communicate, but also connect with and gain the trust of the jury.

While experts may play second fiddle to the inventor in presenting the patentee’s case, they do at a minimum provide the patentee with an opportunity to make up for the inventor’s potential shortcomings if the inventor is not an English speaker or is otherwise not articulate or appealing to the judge or jury. While you cannot pick your inventor, you can pick your expert.

Another key in selecting an expert is finding someone whose specific personal expertise and experience will allow the expert to testify with comfort and conviction. Finding someone with expertise in the field generally may not be enough.

The fact that your witness is a professor at an Ivy League institution, has won multiple awards and has published frequently in prestigious journals does not mean that he or she will be able to speak credibly on the particular questions presented. A Nobel Prize winner who oversees a large lab may not be the best person to critique the performance of a particular assay and someone who has designed human clinical trials may not be optimal in a case that turns on animal testing issues.

Similarly, a brilliant young scientist with a Ph.D. from MIT may not be as effective as a witness who was already working in the field at the time of the invention and can more persuasively attest to what one of ordinary skill in the art would have known at the time of the patent application. Thus, the authors of key pieces of prior art are an excellent place to start your search.

It is important to take the time to try to find an expert with precisely the appropriate professional background as it is so easy for a cross-examiner to cast doubt on even sound testimony offered by an expert who appears to be testifying on matters that are outside their personal experience. The jury may not be in a position to evaluate the substance of the expert’s testimony, but will be keenly aware if the expert is made to squirm while answering a litany of questions aimed at demonstrating what experience the expert has not had.

Stated simply, you do not want to be in a position where you are attempting to cast the expert as something that he or she is not.

A further consideration in choosing an expert is the extent to which you will need or want the expert to be a substantive contributor to the preparation of your case. Experts add more value when they are teaching you than the other way around.

If the technology is unfamiliar to you, you may look to your testifying expert for assistance. A witness who has firsthand experience with respect to what is at issue in the litigation is much more likely to be a meaningful contributor to your case.

Similarly, you will want to determine whether the expert can devote the necessary time to your case. The witness may be a big name in the field, but not have the time or inclination to become immersed in your case.

The bottom line is that witnesses who are not personally familiar with the particular subject matter or have little time for the case may not do much more than sign on to a report that is drafted for them. That will likely become evident to the fact-finder.

Finding a witness with the necessary expertise and ability to communicate is easier said than done. As you focus your search in an effort to find a witness with just the right experience, you will be reducing the pool of available experts from which to choose. This suggests that you should be retaining experts at the outset of the case so as to beat your adversary to the punch.

Moreover, as the field of expertise narrows, the likelihood that an expert knows the inventors or has had some relationship with one of the parties increases. In the pharmaceutical area, lab scientists are likely to have had research grants from one or both of the parties and clinical experts may have worked on clinical trials of the drug in question.

While such relationships will not disqualify the experts, they do raise credibility issues. The expert’s billing rate is also a consideration beyond the obvious one. Jurors, if not judges, may be put off by the amounts that some experts demand.

Arrangements under which witnesses are paid at a higher rate for time spent testifying are particularly disturbing. Again, even jurors that do not understand the substance of an expert’s testimony will appreciate the potential for bias.

An additional, albeit secondary, factor to take into account in searching for an expert is whether you can find an expert who lives and works in the vicinity of the trial court. Being local may be more important than being from Harvard. This probably is a more significant consideration if the court is outside of a major metropolitan area.

Keep in mind that institutions that do not enjoy nationwide recognition are, nonetheless, often viewed highly by local residents. Adding local flavor to your witness list is all the more important if your client and your fact witnesses are not local.

Damages witnesses, a staple of patent cases, present a number of further considerations. For one thing, damages witnesses are more likely to earn their livings testifying. That alone may raise credibility concerns.

Moreover, some damages experts hold themselves out as experts in virtually every field imaginable. The fact that the witness claims expertise in semiconductors, software, pharmaceuticals, chemicals and telecommunications will, in and of itself, be fodder for cross-examination.

To be sure, when I was handling a case involving leachfield chambers used in septic systems, I did not have the luxury of limiting my search to specialists in patent damages relating to septic systems. Presumably none exist.

On the other hand, if you are handling a pharmaceutical case, you can find someone who has personally negotiated licenses under pharmaceutical patents to testify as to the outcome of the hypothetical license negotiation.

The frequency with which some damages experts testify is also an issue because as the expert’s prior testimony accumulates over time it is increasingly likely that something the expert said in the past will come back to haunt him on cross-examination.

Similarly, it is important to attempt to determine whether any court has commented, favorably or otherwise, regarding the expert’s testimony. A few years ago, in preparing for the deposition of my opponent’s damages expert, someone who testifies regularly in patent cases, I found that the expert’s methods had been criticized by several courts. You do not want to learn that too late.

Thus, there are a host of considerations to factor into one’s choice of an expert to testify in a patent case. Inevitably, there are trade-offs to be made. While it will no doubt be tempting to pick the expert who is best known, has won the most awards and has authored the most journal articles that should be the beginning, not the end of your inquiry.


Aaron Stiefel

Aaron Stiefel is a partner at Kaye Scholer in the firm’s New York office.

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