OpenAI has finalized a secondary share sale totaling $6.6 billion, allowing current and former employees to sell stock at a record $500 billion valuation, according to a person familiar with the transaction.

Bloomberg was first to report that the deal had closed.

CNBC reported in August that OpenAI was looking to conduct a secondary share sale at a valuation of $500 billion, with investors including Thrive Capital, SoftBank, Dragoneer Investment Group, Abu Dhabi’s MGX, and T. Rowe Price.

While OpenAI had authorized up to $10.3 billion in shares for sale — an increase from the original $6 billion target — only about two-thirds of that amount ultimately changed hands.

The person briefed on internal discussions said that lower participation is being viewed internally as a vote of confidence in the company’s long-term prospects, and a sign that investor appetite remains strong, even at a $500 billion valuation — up sharply from $300 billion earlier this year.

The offer was presented to eligible current and former employees in early September, with participation open to those who had held shares for more than two years.

The share sale marks OpenAI’s second major tender offer in less than a year, following a $1.5 billion deal with SoftBank in November.

This latest transaction cements OpenAI’s status as the world’s most valuable privately held company, surpassing SpaceX’s valuation of $456 billion.

The sale also comes amid intensifying competition for AI talent. Meta, in particular, has reportedly offered nine-figure compensation packages in a bid to recruit top researchers.

OpenAI is among a growing cohort of high-profile startups — including SpaceX, Stripe, and Databricks — using secondary sales that allow employees to cash out while staying private. The move is widely seen as a strategy to retain talent and reward long-term employees without pursuing an IPO.

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