OpenAI, the artificial intelligence company behind ChatGPT, has received a $1.5 billion investment from SoftBank Group through a tender offer allowing the purchase of shares from current and former OpenAI employees.

The offer will enable OpenAI employees to cash out restricted stock units at $210 per share, allowing employees and stakeholders to receive liquidity during limited initial public offering (IPO) opportunities in tech.

The deal was reportedly driven by SoftBank’s billionaire founder and CEO, Masayoshi Son, who has shown consistent interest in acquiring a larger stake in the AI company, a person familiar with the matter told CNBC.

The funding strengthens OpenAI’s financial resources to advance its AI development while offering liquidity to its stakeholders amid limited IPO opportunities.

Related: OpenAI’s Sora text-to-video tool leaked by aggrieved beta testers

SoftBank expands AI-focused investments

The investment is part of SoftBank’s broader strategy to expand its portfolio in artificial intelligence. In October, it participated in a $6.6 billion funding round for OpenAI.

The tender offer aligns with the Japanese conglomerate’s strategy of investing in and supporting firms that offer forward-thinking tech.

In July, SoftBank invested in another AI firm that aims to retrofit various machines and robotics devices with “general-purpose” brains.

Related: Elon Musk 'shot down’ OpenAI’s ICO plan in 2018 over credibility concerns

OpenAI Sora text-to-video tool leak

OpenAI’s unreleased Sora text-to-video tool was recently leaked by beta testers and artists who made allegations of exploitation during its developmental phase.

The group published access to the unreleased tool online, accusing OpenAI of unpaid labor and a lack of recognition for their contributions.

While OpenAI has since shut down access to the leaked tool, the incident has fueled ongoing discussions about ethical practices in AI research and development.

Related: OpenAI in talks with regulators to become a for-profit company: Report

Copyright lawsuit dismissal

On Nov. 7, a United States federal judge dismissed a copyright lawsuit against OpenAI , filed by news outlets for the alleged misuse of articles in training the firm’s popular ChatGPT tool.

Although OpenAI was cleared for insufficient evidence of harm, the plaintiff’s lawyers stated that they plan to refile the case with additional documentation that they said was “certain” to address the court’s concerns.

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