TL;DR

A US appeals court has overturned the injunction that stopped Perplexity running its agentic shopping software across Amazon’s marketplace. The Ninth Circuit held that Amazon was improbably placed to win its argument that the agents breached federal computer-hacking law, in the first appellate decision anywhere on whether AI agents acting for users may access online platforms.

The reasoning turns on a distinction that will matter well beyond this case. The statute covers accessing computers and taking information without permission. The court decided it was Perplexity’s users, operating through its agents, who accessed Amazon — not Perplexity itself. If that holds, an agent is treated as an instrument of the person directing it rather than an independent actor, which puts a good deal of weight on how the tool is configured and who is deemed to be driving.

Amazon sued in November, alleging Perplexity covertly reached private customer accounts by way of Comet, its browser, and the agent attached to it, which can sign into shopping accounts and place orders. It argued the system created security risks and that Perplexity ignored requests to stop. A California federal judge agreed in March, finding Amazon had presented strong evidence of a breach, and blocked the tool.

Perplexity’s response was less about security than commerce: it called the suit an attempt to keep Amazon customers off Comet because agents cannot see the advertising Amazon serves. Spokesperson Jesse Dwyer framed the appeal as a fight over users’ right to choose their AI. Amazon said it disagreed with the decision on the preliminary injunction, remained confident in its case and was considering next steps — so this is an interim ruling, not a final answer.

Looking Forward

The venue is American, but the question is not. UK retailers building or blocking agentic checkout face the same problem: an automated buyer that bypasses merchandising and advertising while behaving, legally, as the customer. With HSBC UK and Visa having taken agentic payments live last month, UK firms are drafting terms of service against a legal position that is shifting faster than they can revise them.