Carl Zeiss X-Ray Microscopy, Inc. v. Sigray, Inc.

Background

The court addressed four issues that the parties wanted resolved before trial: Sigray’s request concerning certain asserted trade secrets, the scope of Zeiss’s reasonable-royalty damages theory, evidence about post-grant patent proceedings, and Zeiss’s possible rebuttal case.

Sigray’s motion to strike

Sigray argued that the court’s August 20, 2025 order made a factual mistake when it declined to strike ATSs 9 and 12. The court agreed that the earlier order had analyzed Zeiss’s June 2021 trade-secret identification rather than its December 2021 identification, which the parties used for discovery. The court also recognized that Sigray had objected to language in the June identification and that Zeiss later removed that language.

The court nevertheless reaffirmed its decision not to strike ATSs 9 and 12. Zeiss’s expert had offered opinions on those asserted trade secrets, Sigray’s experts had responded, and Sigray had deposed Zeiss’s expert. The court found that this expert discovery made the improper identification harmless. The court therefore did not disturb its decision not to strike ATSs 9 and 12, and it also did not disturb its decision to strike ATSs 13 and 14. The court declined Zeiss’s request to reconsider the ruling concerning ATSs 13 and 14.

Sigray’s motion in limine No. 3: reasonable-royalty damages

The court addressed two royalty-related questions. First, the parties said Zeiss had agreed not to propose a specific royalty amount to the jury because Zeiss had not previously disclosed a calculation for one. The court stated that Zeiss should not be permitted to propose a specific royalty amount indirectly either. Because Sigray’s request was vague, however, the court said Sigray could object at trial if it believed Zeiss was attempting to do so, and the court would rule on the objection then.

Second, Sigray argued that Zeiss could seek a reasonable royalty for patent damages but not for its trade-secret misappropriation claims. Sigray also argued that any trade-secret royalty issue should be decided by the court rather than the jury. The court clarified that its earlier order denying part of Sigray’s motion in limine No. 3 relied on patent-law authorities and addressed reasonable-royalty damages only for patent infringement.

The court found no obvious reason to prevent Zeiss from presenting a reasonable-royalty theory for its claims under the federal Defend Trade Secrets Act and the California Uniform Trade Secrets Act. It noted that both statutes allow reasonable-royalty damages in specified circumstances when actual loss or unjust enrichment cannot be proved. The court also found that Zeiss had not waived the theory because it reserved the right to seek those damages during discovery.

The court did not make a final ruling on the trade-secret royalty issue. It requested more information about the evidence Zeiss intended to present, how it would present that evidence, what limits might apply, whether the jury or the court would apply the Georgia-Pacific factors, and whether the jury or the court would decide the royalty. The parties were told to expect further discussion on August 27, 2025.

Zeiss’s motion in limine No. 4: post-grant proceedings

The court had previously ruled that evidence about post-grant proceedings initiated by Sigray was relevant to whether Sigray had a good-faith belief that Zeiss’s patents were invalid, but that the evidence should be limited to what was necessary to help the jury decide willful infringement.

The court found that Sigray read that ruling too broadly. Sigray could present only evidence necessary to show that it initiated inter partes review and requested ex parte reexamination of the patents asserted in the case. The court excluded the broader presentation Sigray described, including the filings, prior art, and decisions from those proceedings, because that evidence could confuse the jury and require unnecessary trial time.

Rebuttal

The court clarified that it had not decided whether Zeiss could present a rebuttal case. At the final pretrial conference, the court had only declined to give the jury a preliminary instruction about rebuttal evidence. Zeiss may request a rebuttal case at the appropriate time during trial—after Sigray presents its evidence and Zeiss has had the opportunity to cross-examine—and the court will consider the request then.

Disposition

The court did not disturb its prior decisions not to strike ATSs 9 and 12 and to strike ATSs 13 and 14. It limited Zeiss’s ability to propose a royalty amount indirectly, limited Sigray’s post-grant-proceeding evidence, and left the trade-secret reasonable-royalty and rebuttal issues for further consideration. The order does not state a final disposition of the underlying patent or trade-secret claims.