CoreWeave priced its IPO below expectations late Thursday, and the shares edged lower when they began trading Friday. (Michael M. Santiago/Getty Images)

Shares of CoreWeave opened at $39 in their stock-market debut Friday.

The AI startup had priced its offering at $40 a share late Thursday, well below the $47 to $55 range it had been targeting. The scaled back pricing signaled investor concerns about the sustainability of the AI boom that has fueled stock-market gains. Read more here.