A federal judge in San Francisco granted Amazon a preliminary injunction Monday blocking Perplexity from using its Comet browser’s AI agent to access password-protected sections of the Amazon website to shop on behalf of customers.
It’s an early legal milestone in the fast-moving field of agentic commerce, in which AI assistants browse, compare and buy products on behalf of consumers. The case highlights a fundamental question: who controls access when an AI agent shows up at a retailer’s digital front door?
In the ruling granting the preliminary injunction, Senior U.S. District Judge Maxine Chesney found that Amazon is likely to succeed on its claims that Perplexity violated the federal Computer Fraud and Abuse Act and a California computer fraud statute.
The judge drew a key distinction, finding that Comet accesses Amazon accounts “with the Amazon user’s permission, but without authorization by Amazon.”
In its own legal filings, Perplexity had argued that Amazon was less concerned about cybersecurity than about eliminating a competitor to its own AI shopping tools. The San Francisco-based startup contended that AI agents bypass the advertising Amazon shows to human shoppers, and that protecting ad revenue was the real motivation for the lawsuit.
In its suit, Amazon argued that Perplexity deliberately disguised Comet’s AI agent as a regular Google Chrome browser session, evading detection rather than transparently identifying itself.
The company said it warned Perplexity at least five times starting in November 2024 to stop the practice, implemented a technical barrier to block Comet’s access in August 2025, and watched Perplexity release a software update within 24 hours to circumvent it.
“The preliminary injunction will prevent Perplexity’s unauthorized access to the Amazon store and is an important step in maintaining a trusted shopping experience for Amazon customers. We look forward to continuing to make our case in court,” an Amazon spokesperson said Tuesday.
Perplexity has not yet issued a public comment on the preliminary injunction.
In previous statements, the company called the lawsuit “a bully tactic” and argued that consumers should be free to use any AI assistant they choose to shop online. In a November blog post, the company said Amazon should welcome agentic shopping because it means more transactions and happier customers.
Amazon CEO Andy Jassy has acknowledged that agentic commerce “has a chance to be really good for e-commerce” but said agents aren’t good enough yet at personalization and pricing accuracy. Amazon has its own AI shopping tools, including Rufus and Buy For Me.
Under the ruling Monday, the injunction is stayed for seven days to give Perplexity time to ask the Ninth Circuit Court of Appeals to put it on hold while the company appeals the ruling.
The judge denied Perplexity’s request for a $1 billion bond, which it had sought based on its market valuation and investment in Comet. The judge found the injunction doesn’t threaten the entirety of Perplexity’s business since Comet can still be used on every other website.
