Shares of technology companies rose, further paring losses for a volatile week, after an auspicious market debut for SpaceX. Shares of the rocketry and artificial-intelligence company rose by roughly 19% to $161.11.

One strategist said some investors were already placing bearish bets on SpaceX, a dangerous strategy.

"On paper, SpaceX is a short seller's dream setup: massive valuation, complex corporate structure, and a founder who splits his attention across five different companies and is always late on hitting ambitious growth targets," said technology strategist Luke Lango, in a note to clients. "But 'on paper' is doing a lot of heavy lifting. This is a company that controls over half of all global orbital launch capacity, is cash-flow positive, and has Starlink as a genuine recurring revenue machine with 8.5 million subscribers and growing."

The PHLX SOX Semiconductor continued to storm back from last week's historic rout. One hedge-fund manager said the parabolic gains of chip and AI stocks was reminiscent of speculative bubbles, but warned they could continue to behave that way for some time.

"It smells like a bubble and behaves like one, but bubbles can last longer than expected," said Lorenzo Di Mattia, manager of hedge fund Sibilla Global Fund, in a note to clients.