Amazon Wins Court Order Blocking Perplexity AI Shopping Agent

A federal judge in San Francisco handed Amazon a win this week against Perplexity AI, blocking the startup’s Comet browser from making purchases on Amazon on behalf of users—at least for now.

The ruling, issued Monday by U.S. District Judge Maxine Chesney, is a preliminary injunction, not a final verdict.

The broader legal battle over whether AI agents can shop on third-party platforms without the platforms’ consent remains an open question.

The case began in November 2025 when Amazon filed suit against Perplexity under the federal Computer Fraud and Abuse Act and a California computer fraud statute, accusing the startup of disguising Comet’s automated sessions as regular Google Chrome browser traffic.

Amazon said it had warned Perplexity to stop at least five times starting in November 2024.

When Amazon deployed a technical block in August 2025, Perplexity pushed a software update within 24 hours to get around it. The judge cited that move in her ruling.

Judge Chesney found that Amazon provided “essentially undisputed evidence” that Perplexity accessed password-protected Prime accounts with users’ permission but without Amazon’s authorization.

The distinction is the crux of the dispute. Perplexity argued that Comet merely automates what users direct it to do, meaning it inherits the user’s permissions.

The court, at least preliminarily, rejected that logic.

Under the order, Perplexity must stop accessing those accounts and destroy copies of Amazon customer data it already collected through Comet. The injunction is stayed for seven days to give Perplexity time to appeal to the Ninth Circuit.

Perplexity framed its public response around user rights, saying it will “continue to fight for the right of internet users to choose whatever AI they want,” according to a CNBC report on  Tuesday.

In a November blog post, the company labeled Amazon’s legal campaign as “bullying” and argued that agentic shopping would mean more transactions for Amazon, not fewer.

Amazon CEO Andy Jassy previously said in November that agentic commerce “has a chance to be really good for e-commerce,” but argued agents aren’t yet accurate enough on personalization and pricing.

It’s a distinction Amazon used to justify blocking Comet while developing its own tools.

Amazon generated $68.6 billion in advertising revenue in 2025 alone. When an AI agent skips directly to checkout, every sponsored listing between search and purchase disappears.

AI risk

And there’s still the security angle to consider, Amazon argues.

Security researchers at Brave disclosed prompt-injection vulnerabilities in Comet in October 2025, and enterprise analysis found that the browser was more vulnerable to phishing than Chrome.

Amazon cited those findings in its complaint, alongside evidence that it spent more than $5,000, including significant engineering hours, building new detection systems to filter Comet’s automated ad traffic.

Amazon’s founder and executive chairman, Jeff Bezos, is a personal investor in Perplexity. Amazon’s cloud division, AWS, struck a $38 billion infrastructure deal with Sam Altman’s OpenAI on November 3, 2025, one day before the lawsuit against Perplexity was filed.

Amazon has its own AI shopping tools and has separately blocked ChatGPT from shopping on its platform.

Amazon updated its Business Solutions Agreement, effective March 4, 2026, formally requiring all AI agents to identify themselves when accessing its services.

If the injunction stands, it may set an early precedent: platforms can refuse access to AI agents even when users have explicitly authorized it.

How the Computer Fraud and Abuse Act applies to agentic software acting on a human’s behalf has never been tested at trial. That question is now squarely before the court.