OpenAI says its integration with Apple’s Siri has consistently attracted fewer users than expected, according to a court filing in the company’s legal dispute with Elon Musk’s xAI. The claim could weaken xAI’s argument that Apple’s arrangement with OpenAI restricted competitors and harmed its ability to gain customers.

Apple added ChatGPT to Siri in December 2024 through Apple Intelligence. However, users had to complete several steps to enable the service, creating an opt-in process that OpenAI said limited early adoption. By January 2025, the company described the integration as having a slow start and reduced its forecast for the number of additional logged-in weekly active users it expected from the partnership.

OpenAI says Siri integration missed expectations

Large portions of OpenAI’s filing are redacted, but the company says the performance problem became clear by the time Musk’s companies brought their antitrust case against Apple and OpenAI. The filing describes Apple’s integration of ChatGPT as “dramatically underperforming” and later calls it “persistently underperforming.”

OpenAI also refers to a conversation with Apple in March 2026, although the relevant details are redacted. The filing says the limited usage of Apple Intelligence supported OpenAI’s view that the partnership generated minimal activity from users.

OpenAI’s expert, Catherine Tucker, calculated the share of generative AI consumers who accessed ChatGPT through Apple Intelligence using multiple measurements. The filing says those calculations showed only a de minimis level of foreclosure, though the precise figures are redacted.

Apple agreement was not exclusive, OpenAI argues

OpenAI disputes xAI’s claim that Apple and OpenAI entered an exclusive deal. The company says its contract expressly describes the arrangement as non-exclusive and gives Apple the right to add products or services with functionality similar to ChatGPT.

According to the filing, OpenAI requested a two-year exclusivity period, but Apple rejected that request. Apple also told OpenAI that it intended to begin with one provider before adding others. The company later signed an agreement with Google, while Apple’s newest models are based on Google’s Gemini technology, the filing says.

That distinction is central to OpenAI’s response. The company argues that the agreement did not prevent Apple from working with rival providers and that xAI cannot demonstrate meaningful harm when the ChatGPT integration itself produced limited user growth.

What happens next in the antitrust case

Musk’s companies dropped their claims against Apple earlier this month, leaving OpenAI as the remaining defendant in the lawsuit. OpenAI has asked the court to dismiss xAI’s claims before the trial scheduled for January 2027.

The filing does not reveal all of OpenAI’s usage data or the details of its later discussion with Apple. Still, its description of the Siri integration provides a direct account of the company’s expectations and why it now argues that the partnership could not have significantly restricted competing AI services.