Situational Awareness, an investment fund managed by former OpenAI researcher Leopold Aschenbrenner, has officially become the largest shareholder in Nebius. The fund disclosed a 5.6% stake in the company, a position valued at nearly $2.6 billion based on Wednesday’s closing market prices. The sudden influx of institutional buying is on track to push Nebius stock to its highest trading level in over two weeks, News.Az reports, citing Reuters.
Aschenbrenner previously worked at OpenAI as a member of its elite “Superalignment” team, an internal group tasked with developing safety protocols to ensure future superintelligent AI systems remain safely aligned with human values. The specialized unit has since been disbanded by OpenAI leadership.
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The multi-billion dollar bet serves as a powerful institutional vote of confidence for Nebius, validating its position as a critical contender in the rapidly expanding AI hardware and cloud infrastructure race. The company has been experiencing exponential growth, reporting an astonishing eightfold increase in quarterly revenue earlier this month as demand for AI computing power continues to skyrocket.
The investment also highlights the explosive growth of Aschenbrenner’s own firm. Situational Awareness reported managing $13.67 billion in assets as of March 31—representing a staggering 148% expansion since the conclusion of 2025.
