Microsoft Corp. (NASDAQ:MSFT) and Apple (NASDAQ:AAPL) have opted not to participate as board observers at OpenAI, signaling a cautious stance in the wake of increased antitrust scrutiny over Big Tech's involvement in artificial intelligence.

Microsoft, a major investor in OpenAI with a $13 billion commitment, formally announced its decision to withdraw through a letter, citing a reevaluation of its involvement due to the evolving regulatory landscape.

This development comes as European regulators intensify their examination of Microsoft's exclusive arrangements with OpenAI, particularly focusing on how these might affect competition in the burgeoning AI market.

Similarly, in the United States, an antitrust investigation has been initiated to assess Microsoft's potential dominance in this fast-evolving sector.

The absence of board observers from two of tech's largest players follows Microsoft's assertion that the progress made by OpenAI's board over the past eight months has rendered their observer status unnecessary.

Furthermore, Microsoft faces additional regulatory scrutiny over its dealings with Inflection AI, where it spent $650 million for a licensing agreement and absorbed a significant portion of the workforce.

An OpenAI spokesperson confirmed that following Microsoft’s departure, there would be no board observers from any external companies.

This marks a significant shift in the startup's governance dynamics as it navigates a landscape fraught with regulatory challenges and competitive pressures.