The use of expert testimony can be critical in supporting or
defending a patent infringement lawsuit. Given the complex
technical nature of many patent disputes, an expert witness is
typically needed to explain the how the patented features and prior
art would be understood by a person of ordinary skill in the art,
the function and properties of accused techniques, and even the
vocabulary used therein.
But the scope of an expert's testimony is not unlimited. The
Federal Rules of Evidence set forth the requirements for any
testimony that is proffered by an expert.1 These
requirements are the enforced by the trial judge who is empowered
with a "gatekeeping function" that "imposes a
special obligation upon a trial judge to 'ensure that any and
all scientific testimony . . . is not only relevant, but
reliable.'" Carlson v. Bioremedi Therapeutic Systems,
Inc., 822 F.3d 194, 199 (5th Cir. 2016) (citing Kumho Tore
Co. v. Carmichael, 526 U.S. 137, 147 (1999)). The
