CoreWeave, Nebius fall on NASDAQ 100 debut despite rallies

What happened

CoreWeave stock slid 5% to $112 and Nebius stock dipped 1% to $283.50 on their first day in the NASDAQ 100 index. Rocket Lab stock also declined. The three names had climbed sharply before the debut—CoreWeave up 65% year to date through last Thursday, Nebius up 243% year to date, and Rocket Lab up 54% year to date—but traders sold into the well-telegraphed event rather than holding.

Why it matters

Index inclusion normally triggers passive buying that supports share prices, yet these stocks fell anyway, a classic "sell the news" pattern when traders lock in profits after a big run-up. The weakness reflects both profit-taking and a broader market rotation away from growth and AI capital-expenditure exposure; Alphabet stock fell 5% and Amazon stock fell 4% intraday the same day. CoreWeave trades at a price-to-sales ratio of 10x with deeply negative margins, and Rocket Lab carries a price-to-sales ratio of 99x and a beta of 2.5, making them vulnerable when sentiment shifts.

What to watch

Investors can monitor whether CoreWeave and Nebius stabilize into the market close, when passive index funds typically finish rebalancing. A late-day bounce would signal absorption, while continued weakness may suggest the sell-off has further to run. Analysts carry a price target of $140.18 on CoreWeave stock.