OpenAI's Biggest Investor Is Now Listed as a Rival — and One of Its Main Competitors Antitrust regulators have started looking into the Microsoft-OpenAI partnership, and a new detail was slipped into Microsoft's annual report this week.

Microsoft's Tuesday annual report slipped in a new detail — it briefly mentioned OpenAI as a competitor in AI, search, and news advertising, despite Microsoft's $13 billion, years-long commitment to the ChatGPT maker. Microsoft is OpenAI's largest investor.

Microsoft's previous annual report only mentioned OpenAI as a partner, not a competitor. The 2023 report stated that OpenAI exclusively uses Microsoft's cloud services to power ChatGPT; Microsoft, in turn, uses the company's AI models in its products.

Though Microsoft reiterated the partnership in the 2024 report, it added that OpenAI is a rival too.

"Our AI offerings compete with AI products from hyperscalers such as Amazon and Google, as well as products from other emerging competitors, including Anthropic, OpenAI, Meta, and other open source offerings," the 2024 report reads.

Microsoft's search and news advertising business also "competes with Google, OpenAI, and a wide array of websites," per the report.

Related: Microsoft AI CEO Says Almost All Content on the Internet Is Fair Game for AI Training

Microsoft's 2022 annual report only mentioned OpenAI once, as part of Microsoft's Azure OpenAI Service.

^{Microsoft CTO Kevin Scott, right, and OpenAI CEO Sam Altman, left. Photographer: Chona Kasinger/Bloomberg via Getty Images}

In July, Microsoft gave up its OpenAI board seat amid antitrust scrutiny. The U.S. Federal Trade Commission launched an investigation into the Microsoft-OpenAI partnership a month prior, focusing on possible antitrust and data collection issues.

Microsoft's OpenAI partnership took center stage in November during a leadership conflict that spanned five days. OpenAI CEO Sam Altman was removed from his position and decided to join Microsoft to lead a new advanced AI research team.

"I remain confident in Sam and his leadership and capability, and that's why we want to welcome him to Microsoft," Microsoft CEO Satya Nadella told Bloomberg at the time.

Altman ultimately returned to lead OpenAI after 95% of the company threatened to quit unless he came back.

Related: Former OpenAI Board Member Reveals Why She Had CEO Sam Altman Fired