Admissibility standards for patent damages experts has come under scrutiny. Previously, we highlighted the EcoFactor v. Google case regarding Google’s petition for rehearing en banc to address the admissibility of EcoFactor’s damages expert and the parties’ oral argument before the Court. On May 21, 2025, the Federal Circuit issued an 8-2 decision, ordering a new damages trial and overturned the $20 million verdict against Google. The Court found that the district court committed reversible error by allowing EcoFactor’s damages expert to testify at trial.

For anyone following the evolving admissibility standards for expert opinions relating to patent damages, the EcoFactor v. Google case is one to watch. In December 2024, the Federal Circuit granted Google’s petition for rehearing en banc to address the effect of amended Federal Rule of Evidence 702 and Daubert v. Merrell Dow Pharmaceuticals as they relate to admissibility of damages expert testimony—particularly when a per-unit royalty rate is derived from three allegedly comparable lump-sum licenses.