OpenAI has filed a countersuit against its co-founder Elon Musk, accusing the billionaire of conducting a campaign of harassment designed to harm the company and seeking an injunction to stop him from further interference.

In a filing to a California district court on Wednesday, the artificial intelligence company claimed Musk has "tried every tool available to harm OpenAI" through a pattern of actions including "press attacks, malicious campaigns broadcast to Musk's more than 200 million followers on the social media platform he controls, a pretextual demand for corporate records, harassing legal claims, and a sham bid for OpenAI's assets".

The lawsuit specifically alleges that Musk's $97.4 billion offer to acquire OpenAI in February was not genuine and was deliberately intended to disrupt the company's fundraising efforts as it attempts to transition to a for-profit model.

"Musk has engaged in these efforts to slow OpenAI's progress and impair its ability to compete effectively in an increasingly crowded field, but also to seize and maintain for xAI an unearned edge," the filing states, referring to Musk's rival AI company founded in 2023.

OpenAI claims the acquisition offer lacked evidence of available funding and appeared based on "a comedic reference to Musk's favorite sci-fi series" rather than serious business calculations.

Marc Toberoff, Musk's lawyer, defended the bid in a statement: "Had OpenAI's Board genuinely considered the bid as they were obligated to do they would have seen how serious it was. It's telling that having to pay fair market value for OpenAI's assets allegedly 'interferes' with their business plans."

The legal battle stems from disagreements over OpenAI's direction since Musk left the organisation, which was initially founded as a non-profit in 2015. The company's planned restructuring into a for-profit model has been a key point of contention, with OpenAI claiming it needs to complete this transition by the end of the year to secure its current $40 billion fundraising round.

"Elon's nonstop actions against us are just bad-faith tactics to slow down OpenAI and seize control of the leading AI innovations for his personal benefit," OpenAI posted on X, the social media platform owned by Musk.

The case is scheduled to go to jury trial in spring 2026, with OpenAI requesting damages and a permanent injunction preventing Musk from interfering further with its business relationships.

"OpenAI is resilient," the countersuit states. "But Musk's actions have taken a toll. Should his campaign persist, greater harm is threatened – to OpenAI's ability to govern in service of its mission, to the relationships that are essential to furthering that mission, and to the public interest."

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