As the Wisconsin Alumni Research Foundation ("WARF") patent infringement case against Apple approached trial, Apple attempted to call a witness live that it had previously informed WARF's counsel would be called by deposition.

Apple's counsel had previously asked that Patrick McNamara be allowed to appear by deposition in order to accommodate his schedule and not cut into his vacation in order to be called adversely in WARF's case. 

As explained by the district court "over the next two weeks, counsel for both sides confirmed, reconfirmed and reconfirmed again this arrangement." Apparently, on a Sunday night, Apple's counsel, without explanation, indicated for the first time that "Apple will call Patrick McNamara live" during the damages phase.

WARF then moved to enforce the "parties' repeated agreement, indicating that its counsel already planned the presentation of its claim in chief without McNamara being called adversely."

In ruling on the motion, the district court explained that it "normally favors live testimony over deposition testimony, but there is an exception to every rule. Even discounting the specific prejudice to WARF, counsel for both sides are prejudiced generally if they cannot rely on the opposing sides' binding representations."

Accordingly, the court granted the motion to exclude the live testimony "not so much because WARF is likely to be directly prejudiced by his live testimony, but rather because both parties have a right to rely on binding representations in their trial preparation leading up to trial."

Wisconsin Alumni Research Foundation v. Apple, Case No. 3-14-cv-00062 (W.D. Wisc. Oct. 12, 2015)