Amazon fails to block Perplexity's AI shopping tools in court

A federal appeals court overturned a ruling that had temporarily barred Perplexity from using its AI-powered shopping tools on Amazon, keeping the startup’s agentic shopping system active while the lawsuit moves ahead. The dispute, Amazon.com Services LLC v. Perplexity AI, Inc., has become an early test of who controls the AI shopping layer between consumers and the biggest online marketplace.

The case began in San Francisco federal court, where Amazon sued over Perplexity’s Comet browser and its shopping agent. U.S. District Judge Maxine M. Chesney granted Amazon a preliminary injunction on March 10, 2026, temporarily blocking Perplexity from using the tools on Amazon’s platform. On August 4, a panel of the U.S. Court of Appeals for the Ninth Circuit, identified as Milan D. Smith Jr., Eric C. Tung and John Charles Hinderaker sitting by designation, reversed that order and allowed the tools to keep operating while the case continues.

At the center of the fight is a basic question for the AI boom: when software logs in using a user’s credentials, is it acting as an authorized user or as an unauthorized third party? The case tests the limits of the 1986 Computer Fraud and Abuse Act, a law written long before conversational shopping assistants could browse, compare products and move toward checkout on a user’s behalf. Amazon argued the injunction was needed to protect a trusted shopping experience and stop unauthorized access to its store.

The outcome matters beyond one company. Amazon has spent years building a tightly controlled shopping ecosystem built on search rankings, sponsored placements, recommendations and checkout flows. Perplexity’s tools point to a different starting point, one where shoppers may begin with an AI assistant that summarizes options and narrows choices before they ever reach Amazon’s search bar. If that behavior spreads, it could weaken the grip large retailers have over product discovery, traffic and the data that comes with it.

The legal stakes have drawn wider attention from civil liberties and policy groups. The Knight Institute, the American Civil Liberties Union and the ACLU of Northern California filed an amicus brief on April 8, 2026, warning that the dispute raises computer-crime issues for tools that collect information on behalf of users. The ACLU said the legal battle raises “significant Internet freedom issues.”

For now, Amazon’s effort to shut the tools down has failed in court, and Perplexity has kept a foothold in agentic commerce. The broader question remains unresolved: whether AI assistants will be treated as tools that sit inside a user’s account, or as intruders that platforms can keep out.