Index funds tracking major U.S. benchmarks will increase SpaceX holdings after a large insider lockup expires, even as the stock trades above analyst fair value and posts ongoing losses.
U.S. index funds tracking major benchmarks are set to increase their exposure to SpaceX following the expiration of a significant insider lockup, which has made a large batch of shares eligible for public trading. This development comes as SpaceX's stock price has declined 31% since July 2026, and insiders have recently gained the ability to sell, according to Morningstar.
On August 20, 2026, an additional 319 million SpaceX shares-about 7% of insider holdings-became available for trading, further increasing market liquidity and pressure on the stock price.
Index Mechanics and Forced Buying
The next major adjustment will occur with the Nasdaq-100's quarterly rebalance in September 2026, which TD Securities projects could increase SpaceX's index weight from about 1% to over 3.5%. FTSE Russell's next reconstitution is scheduled for December 11, 2026. The newly unlocked shares represent 143% of the 639 million shares that were available to public investors shortly after SpaceX's June IPO, according to Morningstar. If these shares enter the public float, SpaceX's float-adjusted market cap would more than double without any change in the stock price, potentially placing it among the Russell 1000's top 100 holdings at roughly 0.20% of the index-comparable to companies like CVS Health and Pfizer.
Market analysts expect further major unlock events for SpaceX shares in September-October 2026 and again by December 8, 2026, when the main 180-day lockup for some shares expires. These upcoming releases could continue to impact both liquidity and index weights, as more shares become eligible for public trading.
Rapid Entry Into Indexes and Retirement Accounts
SpaceX made its public debut on Nasdaq on June 12, 2026, raising approximately $75 billion at $135 per share in the largest IPO in Wall Street history. Within 15 trading days, Nasdaq's fast-entry rule placed SpaceX in the Nasdaq-100, triggering an estimated $4.3 billion in forced buying from funds tracking the index, according to JPMorgan. FTSE Russell added SpaceX to the Russell 1000 during its June 26, 2026, reconstitution. At July 31, 2026, prices, the float expansion could lift SpaceX's Russell 1000 weight to roughly 0.70% after the December rebalance.
This rapid inclusion means that millions of Americans who never directly purchased SpaceX shares now own a portion of the company through their 401(k) or IRA index funds. For example, Vanguard's $2.3 trillion Total Stock Market ETF held over $3.2 billion in SpaceX as of late June, with that figure set to rise as more shares enter the float. These changes occur automatically and are not typically highlighted on quarterly account statements.
Valuation Concerns and Analyst Skepticism
Despite the surge in index buying, some analysts consider SpaceX significantly overvalued. Morningstar's Nicolas Owens initiated coverage with a fair value estimate of $63 per share before the IPO, lowering it to $62 shortly after. As of August 2026, SpaceX shares were trading at roughly twice that valuation. The company reported second-quarter revenue of $7.8 billion, up 92% year-over-year, but still posted a net loss of $541 million. In 2025, SpaceX lost nearly $5 billion on $18.7 billion in revenue, with heavy losses in its AI segment offsetting profits from Starlink.
Some veteran fund managers have described SpaceX as one of the most attractive short opportunities in the market, citing its high valuation and the structural risk of passive index funds channeling retirement savings into a stock with ongoing losses and uncertain profitability. These concerns are heightened by the fact that index funds must buy more shares as the float expands, regardless of the company's financial health.
S&P 500 Stays on the Sidelines
Not all major benchmarks are following suit. The S&P 500 rejected a proposal to fast-track SpaceX's inclusion in June 2026, maintaining its requirement for a one-year seasoning period and consistent profitability before a company can join the index. This decision means SpaceX cannot enter the S&P 500 before June 2027 at the earliest, and continued losses could delay entry further. The S&P 500 is tracked by about $7.5 trillion in passive assets, with another $3.4 trillion in active funds using it as a benchmark-none of which currently have forced exposure to SpaceX.
What It Means for Retirement Investors
For most retirement savers, these index changes occur behind the scenes. As more SpaceX shares become available for public trading, index funds automatically increase their holdings, even if the stock is trading well above what some analysts consider fair value. This results in millions of Americans increasing their exposure to a volatile and unprofitable company without making an active investment decision. The S&P 500 remains the only major benchmark that excludes SpaceX for now, and actively managed funds still have discretion over whether to hold the stock.
According to Morningstar, the mechanical nature of index rebalancing can create situations where passive funds are required to buy more of a stock just as insiders are selling and prices are falling. Investors relying on index funds for broad market exposure should be aware that these structural effects can sometimes lead to increased concentration in individual stocks, even when fundamentals are in question.
In the second quarter of 2026, SpaceX reported $7.8 billion in revenue and a net loss of $541 million. The company's market capitalization stood at $1.4 trillion as of July 31, 2026, but its float-adjusted weight in the Russell 1000 was just 0.08% before the lockup expiration. The upcoming float expansion could push that weight to 0.70%, significantly increasing index fund exposure.
Index funds are designed to track the performance of a specific market segment by holding all or most of the stocks in a given index. When a company's float-the number of shares available for public trading-increases, its weight in float-adjusted indexes rises, forcing funds to buy more shares to maintain accurate tracking. This process can create buying pressure even when a stock is underperforming or facing skepticism from analysts. For investors, it is a reminder that passive investing is not immune to market quirks and that index composition can shift in ways that may not always align with company fundamentals or long-term value.
