Leopold Aschenbrenner's Situational Awareness LP has acquired 12,410,060 shares of NEBIUS, representing a 5.6% stake in the company as of March 31, 2026. Following this disclosure, NEBIUS shares surged 9.56% in after-hours trading. NEBIUS, a prominent player in AI infrastructure and cloud computing, was spun off from Yandex's international business and is recognized as a leading AI computing stock in Europe.