A qualified expert has to be an expert in the pertinent art. When a technical is-sue, often a factual question, is adjudicated in patent litigation, a court often re-solves such technical issue in view of a person having ordinary skill in the art.203 The Federal Circuit has made some important decisions elaborating the conceptual relationship between “an expert in the pertinent art” and “a person having ordinary skill in the art.”
3.4.1 A Person of Ordinary Skill in the Art
Under Sundance, Inc. v. DeMonte Fabricating Ltd.,204 a qualified expert must be an expert in the pertinent art to be able to testify on infringement or valid-ity. In Sundance, Inc., the defendant introduced its patent attorney as an expert to testify on patent prosecution, claim construction, non-infringement and invalid-ity.205 The district court admitted the defendant’s expert testimony, but the Federal Circuit held the evidentiary ruling was an abuse of discretion.206 On appeal, in-stead of explaining why the patent attorney acquired “the relevant expertise in the pertinent art,”207 the defendant mainly argued that “reliance on a ‘patent expert’
for ‘an opinion on the ultimate question,’ such as infringement or invalidity, is
203 See Rollor, supra note 2, at 321-22 .
204 Sundance, Inc. v. DeMonte Fabricating Ltd., 550 F.3d 1356 (Fed. Cir. 2008).
205 See id. at 1360.
206 See id. at 1361.
207 Id. at 1362.
tirely appropriate.”208 But, the Federal Circuit disagreed.209
The Federal Circuit clarified that the issues of infringement or validity “are analyzed in great part from the perspective of a person of ordinary skill in the art”210 and that “testimony explaining the technical evidence from that perspective may be of great utility to the factfinder.”211 However, the defendant failed to ex-plain how its patent attorney “possesses the relevant expertise in the pertinent art.”212 There was no evidence showing that the defendant’s patent attorney has experiences in the technology at dispute.213 Accordingly, the Federal Circuit held that defendant’s patent attorney was not “qualified as an expert by knowledge, skill, experience, training, or education,”214 and, therefore, that the defendant “fail[ed]
to see how [its patent attorney] could ‘assist the trier of fact to understand the evi-dence or to determine a fact in issue.’”215
While requiring that the proof of infringement, non-infringement, invalidity or validity should be based on “the perspective of a person of ordinary skill in the art,” the Federal Circuit did not use the term “a person of ordinary skill in the art”
to describe the qualification of an expert. Instead, the Federal Circuit held that an expert witness has to be “qualified as an expert in the pertinent art” so as to testify on non-infringement or invalidity.216
Under Sundance, Inc., “an expert in the pertinent art” is not exactly the same
208 Id. at 1361 (quoting the defendant’s brief).
209 See id.
210 Id.
211 Id.
212 Id. at 1362.
213 Id.
214 Id. at 1362.
215 Id. (quoting Rule 702).
216 Id. at 1363.
as “a person of ordinary skill in the art.” On the one hand, the Federal Circuit em-phasized that “[w]e do not, of course, suggest that being a person of ordinary skill in the art automatically entitles a witness to testify as an expert on these or other matters [and] that Rule 702 requires a witness to possess something more than or-dinary skill in the art to testify as an expert.”217 On the other hand, it recognized that “[a] witness possessing merely ordinary skill will often be qualified to present expert testimony both in patent trials and more generally.”218 Therefore, those two terms are either overlapped or independent.
Last, if a witness is not an expert in the pertinent art, as the Federal Circuit held, the witness may neither “testify as an expert as to anticipation, or any of the underlying questions, such as the nature of the claimed invention, what a prior art references discloses, or whether the asserted claims read on the prior art refer-ence,”219 nor “testify as an expert on obviousness, or any of the underlying techni-cal questions, such as the nature of the claimed invention, the scope and content of prior art, the differences between the claimed invention and the prior art, or the mo-tivation of one of ordinary skill in the art to combine these references to achieve the claimed invention.”220
3.4.2 Patent Attorney
The Federal Circuit has clarified that a patent attorney is not a per se expert in patent cases. In Sundance, Inc. v. DeMonte Fabricating Ltd.,221 the Federal Circuit held “[u]nless a patent lawyer is also a qualified technical expert, his testimony on
217 Id.
218 Id.
219 Id. at 1364.
220 Id.
221 Sundance, Inc. v. DeMonte Fabricating Ltd., 550 F.3d 1356 (Fed. Cir. 2008).
these kinds of technical issues is improper and thus inadmissible.”222 Regarding the capability of a patent attorney as a technical expert, the Federal Circuit stated that “patent lawyers are often qualified to testify as technical experts, but such a qualification must derive from a lawyer’s technical qualifications in the pertinent art.”223 Accordingly, a patent attorney who can testify as an expert is not based on his status as a patent attorney but a technical expert who happens to be an attorney.
In addition, a trial judge cannot exclude an expert from testifying simply be-cause he is not a patent attorney. In Outside the Box Innovations, LLC v. Travel Caddy, Inc.,224 the Federal Circuit held that “the exclusion of a technical expert for the reason that he is not a lawyer is contrary to Federal Rule of Evidence 702 and the benefits of technological assistance in resolution of technological is-sues.”225 The holding was based on the nature of patent cases, as the Federal Cir-cuit clarified that “[d]espite the complexity of patent law, patents are not for inven-tions of law; they are for inveninven-tions of technology.”226 So, while recognizing that
“many lawyers have technical training,”227 the Federal Circuit cautioned that “it is technological experience in the field of the invention that guides the determination of obviousness, not the rhetorical skill or nuanced advocacy of the lawyer.”228
3.4.3 Inventor
As illustrated in Federal Circuit case law, an inventor is not equal to a techni-cal expert. The expertise of an inventor must be evaluated case-by-case. In
222 Id. at 1362.
223 Id. at 1363.
224 Outside the Box Innovations, LLC v. Travel Caddy, Inc., 695 F.3d 1285 (Fed. Cir. 2012).
225 Id. at 1296.
226 Id.
227 Id. at 1297.
228 Id.
tricut, LLC v. Esab Group, Inc.,229 the plaintiff submitted one inventor of the pat-ent-in-suit as an expert for testifying on infringement.230 The knowledge about the disputed claim relates to “work function.”231 The Federal Circuit held that the par-ticular inventor was not qualified as an expert under Rule 702 for three reasons.232 First, the inventor “admitted that he was not an expert on the issue of work func-tion.”233 He “had not studied the [work function] at college, and had no graduate degree.”234 Last, he did not acquire “an expert’s knowledge of work function dur-ing the course of his employment.”235
In Air Turbine Tech., Inc. v. Atlas Copco AB,236 while recognizing that the in-ventor “may have particularized knowledge and experience as a co-inin-ventor of the claimed invention,” the Federal Circuit, however, held that “[it] does not necessar-ily mean he also has particularized knowledge and experience in the structure and workings of the accused device.”237 Thus, an inventor may be an expert in the field of his invention, but not an expert in the field of the accused product.