Ninth Circuit Vacates Amazon’s Preliminary Block on Perplexity’s Comet

The court did not resolve the CFAA’s other requirements. The trial court had cited Amazon’s evidence that it spent more than $5,000 responding to Comet, including work to build blocks for private-account access, but the appeals court said it did not need to decide the statute’s loss requirement after finding an error at the earlier access step.

Amazon’s objection was not just a terms dispute

Before Comet’s release, Amazon told Perplexity’s chief executive that it would not permit Perplexity’s AI products to access the store. It repeated that position after the Assistant began doing so. A central technical dispute concerns Comet’s user-agent string: Amazon said an identifier showing that a user had activated an AI agent would allow it to block that access. The parties also dispute whether Perplexity later altered the string after Amazon initially identified and blocked the Assistant.

Amazon’s legal theory was that Comet’s autonomous navigation makes it more than an ordinary browser. The panel agreed that the Assistant does more than passively collect data and that agentic AI has little directly applicable case law. But it found the older precedents offered by both sides imperfect comparisons. The court also said the Assistant is a tool rather than a statutory person, and that Perplexity’s receipt of screenshots and return of instructions, by themselves, did not constitute entry into Amazon’s servers.

The panel also rejected the lower court’s assessment of the remaining injunction factors. It described Amazon’s evidence that Comet could degrade the shopping experience as abstract, and its cybersecurity evidence as limited and partly contested: Amazon’s expert could not fully reproduce every claimed risk, while Perplexity said it had made security improvements. That does not establish that the risks are absent; it explains why the evidence did not support an emergency injunction on this record.

Amazon said in a statement reported after the decision that it disagrees with the ruling, remains confident in its case and is evaluating its next steps.

The next question is control, not AI in the abstract

The case now returns to the trial court. Amazon may seek further appellate review, but the immediate question in the litigation is whether a different factual record could show that Perplexity exercised enough control over the Assistant to gain entry to Amazon’s servers. The Ninth Circuit expressly left that question open, along with potential liability in other settings such as tort claims.

Amazon also retains a route the ruling did not disturb: regulating access to Amazon.com through private terms of service for its users. What the panel rejected was Amazon’s attempt to secure preliminary relief under these two computer-access statutes on the current record. The eventual boundary for AI shopping agents will depend on facts about control and system access, not simply on the label “agent.”