OpenAI CEO Sam Altman has dismissed a US$97.4 billion takeover bid led by rival Elon Musk, but the unsolicited offer could complicate Altman's push to transform the maker of ChatGPT into a for-profit company.

"We are not for sale,” Altman said on Tuesday at an artificial intelligence summit in Paris.

Musk’s bid, announced on Monday, is the latest in a bitter years-long battle with Altman over control of the AI startup they both helped found a decade ago as a non-profit and is now a leading force in the global boom surrounding generative AI technology.

Created as a counterweight to Google's dominance in artificial intelligence, OpenAI got its initial funding from Musk, who invested US$45 million. Three years later, Musk departed OpenAI.

Subsequent lawsuits revealed that OpenAI claimed Musk left after his attempts to become CEO or to merge the company with Tesla were rejected.

After November 2022, when OpenAI released ChatGPT and created a global technology sensation, Musk began criticising the company, trolling it on social media for keeping its source code private and signing a widely publicised manifesto calling for a pause in AI development, even as he pursued his own AI projects.

In August 2024, Musk refiled a lawsuit against OpenAI and its backer Microsoft, claiming the ChatGPT maker had betrayed its founding mission of benefiting the public good in favour of pursuing profits.

Musk later updated the lawsuit to prevent OpenAI's conversion to a for-profit company - a change Altman considers crucial for the company's development.

RTHK's San Francisco correspondent, Mark Niu, said Musk's bid appeared designed to disrupt the company's fundraising efforts.

"The latest reports are that the OpenAI board hasn't even seen that proposal. So it's hard to know what's going on. But there is a real feeling that among investors that Musk is really trying to... tie up things in the courts," said Niu. (AP, additional reporting RTHK)