Overview
- Plaintiff Madison Surber, through Clarkson Law Firm, filed the proposed class-action in U.S. District Court in California after alleging that Oura misled buyers about how accurately its rings identify sleep stages.
- The complaint, filed Aug. 20 and reported widely on Aug. 21, says Oura marketed sleep-staging accuracy figures as high as 79% and 95% while relying on algorithms fed by peripheral signals rather than brain or eye measurements used in clinical sleep studies.
- Oura has disputed the allegations and said it intends to defend against the complaint, and no rulings or settlements have been reported at this early stage of litigation.
- The suit asks a judge to block the disputed marketing claims and to award restitution to customers who paid for rings based on those claims, citing nearly 3 million rings sold and more than $1 billion in revenue in 2025 to show the scale of potential consumer reliance.
- The case highlights a wider technical point about consumer wearables: devices infer sleep stages from heart rate, skin temperature, blood-oxygen and motion signals, which are not direct measures of brain activity used in polysomnography and can produce estimates that differ from lab results.