Order Re Crossroads' Motion To Strike, Quantum Corporation v. Crossroads Systems Inc., Case No. C 14-04293 WHA (Judge William Alsup)

Expert witnesses are often used during patent claim construction to offer extrinsic evidence relevant to the meaning of claim terms, such as how one skilled in the art would have understood the terms at the time of the invention. Yet, experts must be careful to avoid offering opinions on the ultimate meaning of claim terms, which is a question of law. This is a subtle balance that can be tricky to carry out in practice. As Judge Alsup's recent opinion makes clear, an expert must be careful not to cross the line into "gamesmanship" territory when parsing "fact" opinions versus ultimate opinions on claim constructions.

Quantum sued Crossroads Systems, Inc., alleging infringement of a patent related to data storage. Quantum identified Dr. Andrew Hospodor as its claim construction expert who would opine on the meaning of certain claims, a notion he resisted during deposition. Instead, Dr. Hospodor claimed that he was only testifying about matters of fact, i.e., what was known to one skilled in the art at the time of the invention:

Q. So your . . . understanding is here is that you're only here to testify with respect to prior art?
A. My understanding is that I'm here with respect to what was known of one skilled in the art in 2001 and provide facts along . . . those lines.
. . .
Q. But as I understood your prior testimony, you are not going to give an opinion as to the meaning of claim terms; correct?
A. Not in this deposition.
. . .
Q. [Y]ou understand if you don't provide us with the opinions here, you won't be allowed to provide . . . an opinion at the claim construction hearing? Do you understand that?
A. Yeah, I don't . . . know if I'm going to be opining or — either way.
Q. But . . . you don't have opinions today for purposes of this deposition with respect to the meaning of the claim terms in the '412 patent?
A. I'm not going to be providing definitions for the claim terms in the '412 patent. I don't have opinions on the meanings of those claim terms today.

Despite disavowing any ultimate opinion on claim construction during deposition, Dr. Hospodor later submitted a 38-page declaration including "Claim Construction Analysis" and specific definitions for terms, as purportedly understood by persons of ordinary skill, in support of Quantum's opening claim construction brief.

Crossroads moved to strike Dr. Hospodor's declaration and preclude him from testifying on claim construction in rebuttal to Crossroads' own expert, Dr. John Levy. Judge Alsup agreed that Crossroads had put Dr. Hospodor on notice by providing a "summary" of Dr. Levy's opinions, and that Dr. Hospodor should have been prepared to answer questions about such opinions at deposition.

Crossroads also argued that Dr. Hospodor's declaration offered opinions of the nature he declined to provide during deposition. To make matters worse, Dr. Hospodor—in Judge Alsup's words—"vagued out" even when asked to describe the level of ordinary skill in the art, to which he replied: "I haven't created that opinion yet." Quantum's counsel tried to rehabilitate this testimony on redirect, at which point Dr. Hospodor volunteered that one skilled in the art has a bachelor's degree in computer science and at least two years of experience working with tape libraries. Judge Alsup did not take kindly to this inconsistent testimony, remarking that the redirect testimony came "evidently after some woodshedding" by counsel during a break.

Despite Dr. Hospodor's inconsistent testimony and apparent lack of preparedness at deposition to address the opposing expert's opinions, Judge Alsup noted his disappointment that Crossroad's counsel elected to "rest on [Dr. Hospodor's] generic refusal to engage in claim construction" rather than asking "a few pointed questions" to properly subject his opinions to cross-examination. Without the proverbial nail in the coffin, Judge Alsup found the record insufficient to warrant striking Dr. Hospodor's declaration, but ordered that he sit for another three hours of deposition. More significantly, he also left open the door to "the distinct possibilities that the jury will be allowed to learn of Dr. Hospodor's gamesmanships and that the judge will also take it into account on claim construction."

Judge Alsup's order is a cautionary tale of potential pitfalls when navigating the mixed factual and legal terrain of claim construction, and highlights the importance of maintaining consistency with one's expert. While it may not provide a roadmap for the bounds on expert testimony, the order serves as a reminder that developing a full deposition record will generally benefit a party regardless of its side in a subsequent expert challenge.

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