SpaceX draws $12.4B passive buying as Nasdaq-100 lifts weight

About $12.4 billion of passive buying hits SpaceX shares Sept. 21 as a Nasdaq-100 rebalance lifts its weight to roughly 1.51% from 1.25%.

"The real test comes in November, when the earnings-triggered unlock puts a large volume of shares into the market," said Ed O'Gorman, chief executive at River Wealth Advisors.

JPMorgan strategist Min Moon's team estimated the buying after SpaceX's free-float ratio jumped to about 30% from under 10% once more than 1 billion shares left lockup. Worth more than $2 trillion and the index's sixth-largest member, SpaceX had ranked 19th by weight at 1.25%. Roughly $1.7 trillion tracks the Nasdaq-100, including Invesco's QQQ ETF, and Bloomberg has put the potential demand as high as $15.5 billion. The rebalance plan is due Friday after the close.

The buying is mechanical, not a verdict on fundamentals — and the same unlock process that set it in motion is far from over. More than 2.3 billion shares unlock by mid-November, about 1.3 billion of them after third-quarter earnings, and whether insiders sell into the index-driven demand will shape the stock's fourth-quarter path.

A Free-Float Rule, Not Fundamentals, Drives the Buying

The Nasdaq-100 caps a member's weight at the lower of its total shares or three times its free-float shares, so stocks with heavily restricted floats are discounted in the calculation. SpaceX was exactly that case: locked-up stock kept its float under 10%, and despite a market value above $2 trillion it carried just a 1.25% weight. Once more than 1 billion shares unlocked, the float rose to about 30% and the index recalculated the weight upward.

The mechanism is not unique to Nasdaq. S&P Dow Jones Indices also weights by free-float-adjusted market value; Piper Sandler estimated roughly $40 billion of passive buying after Berkshire Hathaway cut its Apple stake two years ago. SpaceX joined the Russell 1000 in June, but the S&P 500 requires at least 12 months of trading history, so the earliest it could qualify is mid-2027 — leaving room for further index inflows later.

The 2.3-Billion-Share Supply Wave Comes Next

The float jump is itself the product of an unlock, and bigger tranches are scheduled. More than 1 billion shares become tradable before the end of October, with about 1.3 billion more following the third-quarter report in mid-November — over 2.3 billion combined. August's first unlock, which coincided with SpaceX's debut earnings, raised fears of heavy selling, but insiders largely held their stakes and the pressure did not materialize.

Interactive Brokers chief strategist Steve Sosnick said newly unlocked shares will either be absorbed by the passive buyers or push the price higher as index funds add demand. SpaceX has traded in a $133-to-$150 range over the past four weeks, hovering near its $135 IPO price, and closed Tuesday up 0.06% near a two-month high.

The November unlock is the moment that separates mechanical support from genuine demand. If insiders hold again, the $12.4 billion rebalance flow could carry the stock higher; if they sell, the passive bid becomes a buyer of last resort rather than a floor. Until then, the price action reflects index arithmetic more than conviction about the company.

This article is for informational purposes only and does not constitute investment advice.