Fluidstack, a startup that builds specialized data centers for AI companies, is in talks to raise a $1 billion round at an $18 billion valuation, potentially led by Jane Street, Bloomberg reports. Should this deal come to fruition, it would more than double Fluidstack’s valuation in a matter of months. In December, the company was reportedly raising around $700 million at a $7.5 billion valuation, sources told Bloomberg at the time, although it didn’t formally announce the close of that round.