How to Be an Effective ChemE Expert Witness in IP Lawsuits: Part 2

Acting as an expert witness in intellectual property disputes requires significant preparation and work. Chemical engineers should know what to expect, how to market themselves, and what pitfalls to avoid.

The first part of this two-part series, published in the June 2025 issue of CEP (pp. 48–53), described the role chemical engineers can play as expert witnesses in legal disputes involving intellectual property (IP) — particularly, patent and trade secret rights. This article provides further guidance on fulfilling your role as an expert witness and how to market yourself as an expert, as well as examples of real-world expert witness work.

What to expect

Compensation. As mentioned in Part 1, you will be compensated for your work as an expert witness. Almost always, compensation is in the form of an agreed hourly rate, which you will bill to the party retaining you or to the party’s legal counsel, much as a technical consultant would bill their work. Your engagement agreement should make clear that your compensation is not dependent upon your ultimate conclusions or opinions; otherwise, you would seem biased, thus harming your persuasive power.

Because of their complexity and high risks, IP disputes often merit relatively high rates of compensation compared to other disputes. Novice expert witnesses in IP disputes typically charge rates around several hundred dollars per hour. Experienced experts with an established track record often charge higher rates, reaching $500 per hour or more. The exact rate you can demand (or a prospective client will offer you) will depend on your level of experience, the uniqueness of your technical expertise, and the importance of the dispute to your prospective client.

Workload. Your workload as an expert witness will be highly variable, often with long periods of relatively stable activity (or no activity at all) punctuated by short periods of intense, time-consuming work. Lawsuits are very deadline-driven, and those deadlines can change in unexpected ways. Although legal counsel will try to keep you abreast of the relevant deadlines and ensure that your work is done in a timely manner, you should expect the unexpected and be prepared for the need to undertake work on short schedules that might conflict with other professional and personal demands. Close collaboration with legal counsel and disclosing your other demands can help mitigate such scheduling conflicts.

Retention as an expert witness can be a long-term commitment. While patent proceedings at the International Trade Commission (ITC) and Patent Trial and Appeal Board (PTAB) are often concluded in 1–2 years (and your active role may be shorter than that) (Figure 1), patent and trade secret infringement lawsuits in federal courts can last 2–3 years or longer (Figure 2). Therefore, when undertaking work as an expert, you should plan far into the future. Carefully consider whether changes in your schedule over the next several years (for example, due to new employment) might impact your ability to conclude an engagement. Also note that as a lawsuit proceeds, a party’s ability to retain new experts to replace experts who can no longer continue working on their behalf can become constrained. You should expect that a client will not be able to replace you once a lawsuit has reached an advanced phase, at which point you will need to see the engagement through to the end.

---

▲Figure 1. In a PTAB Trial, the petitioner and the patent owner (PO) employ their own expert witnesses to support their positions seeking to invalidate or defend, respectively, the validity of the patent(s) subjected to trial. Patent expert witnesses are retained to provide written reports that become part of the body of evidence used by the Patent Trial and Appeal Board (PTAB) to re-assess the validity of previously granted U.S. patents. PTAB trials have shorter timelines than infringement lawsuits in federal court. Visual strategy and design source: LPI.

---