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Key Evidentiary Rulings in Acceleration Bay v. Activision

In the ongoing patent infringement case between Acceleration Bay LLC and Activision Blizzard Inc., the district court recently issued an order resolving several important evidentiary disputes between the parties. This order provides guidance on the admissibility of various categories of evidence that will impact the damages case at the upcoming trial.

Here are the key takeaways:

Survey Evidence Allowed for Limited Purpose

The court permitted Acceleration Bay to use Activision’s own customer surveys for the limited purpose of showing that the allegedly infringing large multiplayer game modes in Call of Duty are of equal or greater importance to customers compared to the non-infringing small game modes. Nonetheless, the district court reiterated its exclusion of the plaintiff’s damages expert’s opinions apportioning royalties based primarily on this survey evidence, finding that while the surveys can demonstrate the significance of the accused modes, they cannot directly calculate the royalty damage amount.

Evidence of Foreign World of Warcraft Sales Permitted

The district court allowed Acceleration Bay to present evidence of Activision’s foreign sales revenues for the World of Warcraft game. The plaintiff’s theory is that the infringing U.S.-based server system supports foreign players in North and South America. The district court found that as long as Acceleration Bay provides evidence linking the foreign sales to the accused domestic server system, the foreign revenue numbers can be admitted, even if conditionally at first.

Prior Offers to Sell Patents Admissible

In a win for Activision, the district court ruled that evidence of the prior patent owner Boeing’s $1 million offer in 2010 to sell the asserted patents is admissible. This allows Activision to argue that the patents’ value was set by Boeing’s own willingness to sell them for that amount. Importantly, the district court found that Activision cannot present evidence that Boeing’s offers were rejected, as that could unfairly prejudice the jury.

Total User Numbers Allowed

The district court permitted Acceleration Bay to introduce evidence of the total number of users for the Call of Duty and World of Warcraft games. While not a direct royalty calculation, the district court found this evidence is relevant to the commercial success and profitability of the accused games.

Streamlined Revenue Data Permissible

Finally, the court allowed the plaintiff to present World of Warcraft revenue data in a streamlined, annualized format rather than being forced to use Activision’s original quarterly breakdown. This simplified presentation was deemed acceptable even if it could obscure revenue trendlines that Activision wanted to emphasize.


This order provides a detailed preview of what evidence will and won’t make it to the jury in this high-stakes patent damages trial. The rulings carefully balance allowing relevant financial evidence while preventing any unfair prejudice. Stay tuned as the parties head toward the pivotal trial in this long-running litigation.

ACCELERATION BAY LLC, v. ACTIVISION BLIZZARD INC., Case No. 16-453-WCB (D. Del. April 28, 2024)


The authors of are patent trial lawyers at Jeffer Mangels Butler & Mitchell LLP. For more information about this case, contact Stan Gibson at 310.201.3548 or