The Collapse of Capability Theory: Ambriz, Popa, and the Future of Article III Standing in AI Privacy Cases
Caroline Aiello
Introduction
In February 2025, the Northern District of California denied Google’s motion to dismiss in a class action lawsuit that claimed Google’s artificial intelligence (“AI”) tools violated the California Invasion of Privacy Act (“CIPA”) by transcribing phone calls of users.[1] The court in this case, Ambriz v. Google, ruled that Google’s technical “capability” to use customer call data to train its AI models was enough to state a claim under California’s Invasion of Privacy Act, regardless of whether or not Google actually exploited that data.[2] Six months later, the Ninth Circuit took the opposite approach. The later ruling in Popa v. Microsoft held that routine website tracking did not constitute actual harm and the claims were dismissed for lack of Article III standing before reaching the merits.[3]
These two decisions present privacy law with incompatible standards. Ambriz asks what a technology could do with personal data and finds liability in that potential. Popa demands proof of what a technology actually did and requires concrete injury beyond the action itself. The collision between the two theories is inevitable. When a plaintiff sues an AI company under Ambriz’s capability theory, alleging that the defendant’s system has the technical ability to misuse data, and the defendant responds with a Popa-based standing challenge, the courts will face an impossible choice. The capability to cause harm is not the same as harm itself, and if capability cannot satisfy Article III’s concrete injury requirement, then Ambriz’s approach becomes constitutionally unenforceable in federal court. While Popa has not technically overruled Ambriz, the Ninth Circuit will inevitably need to choose which standard to adopt.
