The Claim Was There. The Proof Wasn't.
Deque Systems Inc. v. BrowserStack, Inc., 2026 WL 1615177 (4th Cir. 2026)
This case is a good reminder that even a strong business dispute can fall apart if a party does not properly disclose its damages during discovery. Deque and BrowserStack are competitors in the web accessibility software market. Deque sued BrowserStack for copyright infringement, false advertising, breach of contract, and unjust enrichment. Deque claimed BrowserStack copied parts of Deque’s software and related materials when developing its own accessibility testing product. Deque also claimed BrowserStack made false statements comparing its product to Deque’s. But as the case moved through discovery, Deque repeatedly failed to provide a clear calculation of the damages it sought, even after BrowserStack requested that information and after the court’s deadlines had passed.
The district court responded by excluding Deque’s damages evidence as a discovery sanction. The Fourth Circuit affirmed that decision. The court explained that Rule 26 required Deque to disclose how it was calculating each category of damages and to provide the supporting materials on time. Instead, Deque delayed for months and did not clearly reveal its damages theory until just before discovery closed, when its expert report claimed damages of more than $30 million. The Fourth Circuit agreed that this late disclosure unfairly surprised BrowserStack, could not be fixed without reopening discovery and delaying the case, and had no adequate justification. Because of that, the district court acted within its discretion in blocking Deque from using that damages evidence.
Deque argued that its copyright and false advertising claims should still survive because it had also asked for injunctive relief. The Fourth Circuit rejected that argument too. The court said Deque had no evidence of any ongoing or future infringement or false advertising. The record showed that the earlier product version Deque challenged was no longer being sold, the current version was not shown to be infringing, and the allegedly false advertising had been removed from BrowserStack’s website. So even aside from the damages problem, Deque had no viable path to the other relief it wanted.
For businesses, the lesson is simple: if you want to recover substantial damages, you need to clearly and on time disclose your damages theory; and if you want an injunction, you need evidence that the harmful conduct is still happening or is likely to happen again.
This post is for informational purposes only and does not constitute legal advice. If you have questions about your specific situation, you should contact a lawyer for assistance. Nothing herein is intended to create any attorney-client relationship between you and DLM LAW.
