The news: Amazon's decision to block Meta's Muse from shopping on its site escalates a fight over who controls the relationship with shoppers as AI agents move into product discovery and purchasing.

Amazon started blocking Meta’s Muse agent from shopping on its website, per GeekWire, claiming the agent is unauthorized because it doesn’t declare itself and could acquire customer credentials, raising privacy concerns.

Why it matters: Third-party AI agents could weaken Amazon’s ability to collect first-party data on shoppers—a critical component of its ad business, which we expect will surpass $83 billion in revenues this year.

When third-party AI agents such as Muse visit Amazon, they perform activities normally left up to shoppers, such as viewing product pages and clicking on related items. That could hurt Amazon’s ability to tie those behaviors to individual consumers and feed that data back into targeting ads.

AI agents are capable of circumventing ads entirely, which is another reason why Amazon wants to block them. If brands can’t ensure their ads are reaching the right audiences—or being seen at all—they will have less reason to advertise on Amazon.

Meta isn’t the first tech company to challenge Amazon’s control over agentic shopping. Last year, Amazon blocked Perplexity’s Comet browser for the same reasons, a tiff that eventually went to court. Last month, a court of appeals vacated an injunction in favor of Perplexity, allowing Comet to shop on the site. The case isn’t fully closed for Amazon, but this month the court rejected its motion for a rehearing.

Worth noting: Meta has a pre-existing relationship with Amazon that could influence the outcome of the disagreement.

In 2023, Amazon began allowing consumers to buy its products through ads shown on Instagram and Facebook without leaving the social media apps. More recently, Meta became one of the largest customers of Amazon Web Services’ Graviton AI chips.

Those ties could give both companies reason to come to a compromise before the issue winds up in court.

Implications for marketers: AI shopping agents could disrupt the targeting and ad exposure that support retail media ecosystems, and marketers will have to keep abreast of updates as new rules are established. If Muse gets access to Amazon in the same way as Perplexity's Comet, it may be time to reconsider ad strategies for the ecommerce platform.

Of course, Meta could back off, or a compromise could be reached allowing Amazon to retain its ability to gather first-party data. Marketers should request transparency from Amazon, such as how agents affect ad targeting and which specific agents it intends to allow on its site (Amazon CEO Andy Jassy has previously said the company is open to partnerships with third-party shopping agents, per The Information).

Regardless of how this dispute shakes out, brands should prepare for more shopping activity to move from consumers to AI agents acting on their behalf. That means marketers should focus on what they can control: optimizing content for generative engines, both on third-party ecommerce platforms and owned websites.

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