The three founders of CoreWeave will spend the next few weeks trying to sell investors on the cloud provider's future. What might make that job harder: They've already cashed out nearly a half-billion dollars from their stakes, between them.

The founders—former commodities traders Mike Intrator, Brian Venturo and Brannin McBee—have each sold at least $150 million worth of stock ahead of the cloud provider's planned initial public offering, the company's IPO prospectus showed Monday. The share sales are unusually high for startup founders ahead of a public offering.