Microsoft has relinquished its observer seat on the board of OpenAI, while Apple will not be taking up a similar role, amid increasing global regulatory scrutiny of Big Tech’s investments in AI startups.

Microsoft, which has invested $13 billion in OpenAI, the creator of the ChatGPT chatbot, announced in a letter to OpenAI that its board role withdrawal was “effective immediately.”

Apple was anticipated to take an observer position on OpenAI’s board as part of a deal to integrate ChatGPT into its devices, but will not proceed, according to a source familiar with the situation. Apple declined to comment.

OpenAI will instead hold regular meetings with partners like Microsoft and Apple, as well as investors Thrive Capital and Khosla Ventures, as part of a “new approach to informing and engaging key strategic partners,” said an OpenAI spokesperson. This strategy is led by Sarah Friar, the former Nextdoor CEO, who was recently appointed as OpenAI’s first chief financial officer.

This decision comes as antitrust authorities in the EU and US examine the Microsoft-OpenAI partnership amidst broader concerns about competition in the fast-growing AI sector.

Microsoft had accepted a non-voting board role following last year’s turmoil at OpenAI, when CEO Sam Altman was abruptly dismissed and then quickly reinstated. The boardroom upheaval had threatened OpenAI’s valuation and Microsoft’s significant investment in the company.

“This position provided insights into the board’s activities without compromising its independence,” Microsoft’s deputy general counsel Keith Dolliver wrote to OpenAI. With significant progress from the new board, Dolliver noted that Microsoft’s role was no longer “necessary,” but emphasized that OpenAI remains a valued partner.

Microsoft’s partnership has been crucial to OpenAI’s success, providing computing power and cloud storage worth billions. Microsoft CEO Satya Nadella played a key role during the boardroom crisis at OpenAI in November.

Investing in OpenAI has given Microsoft a lead in the generative AI race, significantly boosting demand for its AI services and accelerating sales for its Azure cloud platform over the past three quarters.

Microsoft does not hold a traditional equity stake in OpenAI but is entitled to a share of profits from a subsidiary of OpenAI, up to a certain limit. OpenAI’s website states it remains an independent company governed by the OpenAI Nonprofit.

In light of growing antitrust concerns, both Microsoft and OpenAI have downplayed their ties. The European Commission in June considered an antitrust investigation into their partnership, while the US Federal Trade Commission has also begun examining investments by Big Tech companies like Microsoft, Amazon, and Google into generative AI startups.

An OpenAI representative stated, “We appreciate Microsoft’s confidence in our board and company direction, and we are eager to continue our successful collaboration.”

The OpenAI board comprises eight members, including CEO Sam Altman, former US Treasury Secretary Larry Summers, and Instacart CEO Fidji Simo. The board is chaired by Bret Taylor, former co-CEO of Salesforce and co-founder of the AI startup Sierra.