The Vanguard Communication Services ETF (VOX) has increased its stake in Space Exploration Technologies (SpaceX) by 85.2% in two months. That stake could eventually grow to as much as one-fifth (20%) of the fund once SpaceXs shares fully unlock.
VOX held 632,077 SpaceX (SPCX) shares on June 30, a total that reached 1,170,398 by Aug. 31. That makes SpaceX the funds eighth-largest holding, though Vanguard has not disclosed the exact share of VOX it now represents.
Is This SpaceX Concentration a Problem Hiding in Plain Sight？
SpaceX debuted on the Nasdaq on June 12, 2026, with only about 5% of its shares available to trade. Each new share unlock since then has expanded that float and, with it, SpaceXs weight inside float-based indexes.
The Nasdaq-100 weights SpaceX using a multiple of its float, not its full market cap. That formula applies until the float grows large enough. As more shares unlock, the float grows, and so does SpaceXs index weight.
SpaceXs performance has been far from impressive in its entire lifetime. Image Source: Trading View
VOX has ridden that mechanic more aggressively than its Vanguard peers. Other Vanguard funds have barely touched SpaceX by comparison.
A Payoff Has to be Coming？
SpaceX has not cracked the top 50 holdings in the Vanguard Growth ETF. It is also outside the top 100 in the Vanguard Total Stock Market ETF. Vanguards Total World Stock ETF keeps it outside its top 200 as well.
Vanguard classifies SpaceX exclusively as a communications stock. That means its full weight lands inside VOX alone.
Alphabet and Meta Platforms already make up 42.4% of the fund. Add a fully weighted SpaceX, and VOXs top three holdings could account for well over half the portfolio.
Investors already saw that kind of swing when SpaceXs Starship milestone sent the stock up 6% in a single session.
So how much of one still-volatile, newly public stock belongs inside a single sector fund？
VOX‘s bet pays off if SpaceX keeps executing. But it means the fund’s returns increasingly hinge on one still-newly public stock. That risk stacks on top of an already top-heavy bet on Alphabet and Meta.