(Reuters) -Nebius Group's ( NBIS ) shares soared nearly 50% to $95.7 on Tuesday as investors cheered its $17.4-billion deal supplying AI infrastructure to Microsoft ( MSFT ) over a five-year period.

The partnership comes amid an unprecedented surge in demand for artificial-intelligence data centers, as businesses accelerate the race to build more advanced generative AI technologies.

The stock, which has more than doubled this year, rose 49.5% in premarket trading, while shares of rival CoreWeave ( CRWV ) were up 6.3%.

Nebius ( NBIS ) is set to add around $7.7 billion to its $15.3-billion market capitalization, if gains hold.

"We continue to believe that Nebius ( NBIS ) is well set up to bring on other high-profile customers, including other hyperscalers or frontier AI labs, as the company continues to build out their data center capacity with upcoming greenfield opportunities," said Alexander Platt, analyst at DA Davidson.

Microsoft ( MSFT ), which has repeatedly flagged a shortage of AI cloud infrastructure due to soaring client needs, has been turning to third-party providers to bridge the gap.

The tech major has a similar multibillion-dollar deal with CoreWeave ( CRWV ), which also has a substantial contract with OpenAI for AI computing resources.

Nebius' ( NBIS ) core business consists of providing clients with full-stack AI cloud services built on Nvidia ( NVDA ) computing, giving AI developers the software and hardware tools and services needed to build and run their models.