United Kingdom, Oct. 3 -- OpenAI has surged past SpaceX to become the world's most valuable privately held startup after completing a secondary share sale that values the ChatGPT maker at around $500 billion.

According to Bloomberg, the deal allowed current and former employees to sell approximately $6.6 billion in shares - a transaction that pushed OpenAI well ahead of Elon Musk's SpaceX, which was last estimated at around $400 billion.

In its announcement, OpenAI said it had finalized the share sale, marking a new valuation milestone in its rapid growth trajectory.

The company previously raised capital at a $300 billion valuation earlier in 2025, making this jump a dramatic increase.

Beyond the valuation leap, the sale underscores t...