A federal court ruled this month that an AI agent doesn't need Amazon's, or any retailer's, permission to shop its site.
The Ninth Circuit cleared Perplexity's Comet agent to buy from Amazon without the retailer's sign-off. For brands, the split is now explicit: ChatGPT and Gemini still require opt-in feeds, but Perplexity has already made the decision for you.
A federal court ruled this month that an AI agent doesn't need Amazon's, or any retailer's, permission to shop its site.
This is the first in a short series unpacking the different types of agents now shaping how, and whether, brands get chosen. The intention is to explain the nuances across the different AI agents because most brands are treating them as one when they're not. We're starting with the category most people are familiar with, the consumer-facing AI apps, ChatGPT, Gemini, Claude and Perplexity.
The objective across all four looks identical: get found, get recommended, get bought. What actually differs is whether your brand gets a say in the matter, and what it costs you when it does.
ChatGPT and Gemini both work on opt-in permission. Products only surface if the underlying feed is built for it, ACP for ChatGPT, UCP and AP2 for Gemini. The catch most brands miss: having a feed already running for paid Shopping ads doesn't mean you're covered. Much of that same data does feed AI recommendations, but a feed optimised to win an ad auction is not structured the way these systems weight results (attribute completeness, reviews, return policy, descriptive detail). Same file, different job and most feeds haven't been rebuilt for the second one.
Even done properly, opting in doesn't mean you keep control of what happens next. Google's Universal Cart pulls products from Search, Gemini, YouTube and Gmail into one persistent cart. The retailer stays merchant of record and keeps the sale. What it loses is everything around the sale, the search intent, the comparisons, the products that almost got picked, because the entire journey happens on Google's surfaces, not the retailer's own site or app.
Perplexity skips the opt-in step entirely. Its Comet browser agent logs into sites and buys the way a person would, using stored credentials, whether or not the brand has fed it anything. Amazon sued to stop it, won a preliminary injunction in March, then lost on appeal this month. The Ninth Circuit found it's the user, not Perplexity, accessing Amazon's systems, so Comet is back shopping there today. The early legal read is that an agent acting for a shopper doesn't need the retailer's sign-off at all.
Claude isn't playing this game yet. Anthropic has piloted agents negotiating purchases internally, but hasn't built a consumer checkout to rival the other three. Its commerce push sits on the enterprise side, agents handling procurement for businesses, not shopping for consumers.
With ChatGPT and Gemini, showing up is still a decision your brand makes, and getting it right takes real work most feeds haven't done yet. With Perplexity, that decision has already been made for you.
- —A federal appeals court ruling means Perplexity's Comet agent can shop retailer sites without permission — the opt-in model no longer applies everywhere.
- —ChatGPT and Gemini still require structured, opt-in feeds; most brands' existing Shopping feeds aren't built for AI recommendation weighting.
- —The agent landscape is splitting: control what you can on opt-in platforms, and accept that Perplexity-style agents are already shopping your site regardless.