Nebius Group N.V. (NBIS) launched its AI Cloud 3.1 platform on December 17, 2025, integrating next-generation NVIDIA Blackwell Ultra compute. The company highlighted being the first globally to run production GB300 NVL72 systems on 800 Gbps InfiniBand, enhancing its AI infrastructure. NBIS stock saw volatility, including a 6.79% dip on December 17 due to Q3 revenue missing estimates and sector leverage concerns. However, shares rebounded significantly, rising 14.56% on December 19 and 4.21% on December 22, fueled by optimism over major contracts with Microsoft and Meta, and ongoing acquisition speculation.