SpaceX IPO: What Index Funds Will Buy, When, and Should Retail Investors Invest?

Ben Felix

The SpaceX IPO, At a Glance [00:40]

SpaceX's Initial Public Offering (IPO) is poised to be historically massive, both in terms of capital raised and market capitalization at the time of its debut. To ensure its success, SpaceX has pursued two key strategies:

• Rule Changes for Index Inclusion: SpaceX has lobbied for rule adjustments that would permit its almost immediate entry into major stock market indices.
• High Retail Investor Participation: The company aims to allocate approximately 30% of its IPO shares to retail investors, a significant increase compared to the typical 5-10% seen in other IPOs.
  • These initiatives have been largely successful, with many index providers modifying their rules and retail brokerages actively promoting direct investment in the SpaceX IPO. This has led to expectations of an oversubscribed IPO, where demand exceeds available shares.

    

Index Rules & SpaceX Inclusion [01:38]

The recent trend of major indices altering their rules in anticipation of large IPOs like SpaceX has been a significant development in finance.

• Evolution of Index Rules: Indices typically have rules governing the inclusion of new companies, such as waiting periods for IPOs and requirements for "free float" (the proportion of shares available for trading).
• The "Passive" Myth: While index funds are considered "passive" for tracking rules-based indices, changes to these rules indicate an active decision-making process within the indexing world.
• SpaceX's Motivation for Early Inclusion: SpaceX desires rapid index inclusion because index funds mechanically purchase included stocks, which supports the stock's price and often leads to a jump in value before inclusion.
• Index Providers' Responses:
  • NASDAQ, FTSE Russell, and S&P initiated consultations on potential rule changes.
  • NASDAQ and FTSE Russell ultimately adopted changes to facilitate earlier inclusion for large IPOs.
  • S&P, to everyone's surprise, decided not to change its rules for the S&P 500 and other core indices.

    

The Nasdaq 100 [04:07]

The NASDAQ 100, which tracks 100 leading non-financial companies listed on the NASDAQ exchange, has historically had specific inclusion criteria.

• Previous NASDAQ 100 Rules:
  • New companies were typically added during annual reconstitution in December or as replacements.
  • A three-month "seasoning period" was required before a company could be included.
  • A 10% free float requirement was in place, which would exclude SpaceX (expected initial free float of 4%).
• Adopted Changes:
  • Accelerated Inclusion: Inclusion is now permitted after the 15th trading day for stocks ranking in the top 40 by total market capitalization. This allows mega-cap companies like SpaceX to enter much sooner.
  • Free Float Requirement Removed: The 10% free float rule, only added in June 2024, was removed.
• Unique Weighting Methodology:
  • Unlike most indices that use free-float weighting, the NASDAQ 100 is weighted by total market cap (including unlisted insider shares).
  • For low-float stocks, a cap of three times the free float will be used for weighting, rather than the full total market cap or just the free float.
  • This means SpaceX will be weighted higher than in most other float-weighted indices, but lower than its full total market cap, addressing liquidity concerns.

CRSP & MSCI Indices [07:07]

Other major index providers, CRSP and MSCI, already had fast-track inclusion rules or made subtle changes.

• CRSP (Vanguard's VTI ETF):
  • Existing Fast-Track: CRSP's Total Market Index (tracked by Vanguard's VTI ETF) has long allowed FastTrack inclusion after only five trading days for eligible IPOs.
  • Quiet Free Float Change: CRSP quietly adjusted its free float requirement from a flat 10% to "10% or 0.005% of the float-adjusted capitalization of the index eligible universe," which was $3.3 billion in March 2026. This change enables mega-cap, low-float IPOs like SpaceX to be included.
  • SpaceX's Weight: Due to its low free float, SpaceX is estimated to constitute a small portion of the CRSP US Total Market Index initially (e.g., 0.12%), but its weight could increase as more shares become available.
  • Early Share Release Provisions: SpaceX's IPO includes provisions for early release of restricted shares in stages, deviating from a traditional 180-day lockup:
    • 20% after the second trading day following the earnings release.
    • An additional 10% if the stock trades 30% above its offering price for five of ten consecutive days ending on the first earnings release.
    • Further blocks of 7% at 70, 90, 120, and 135 days post-listing.
    • Another 28% after the Q3 earnings report, with any remaining shares released after 180 days.
  • Critiques of Fast-Track Inclusion: There is evidence suggesting that traders exploit CRSP's FastTrack methodology by buying shares before inclusion, driving prices up, only for them to drop after inclusion, effectively costing index fund investors.
• MSCI:
  • MSCI has not made recent changes, as its rules already allowed for the fast-track inclusion of large IPOs.
  • Their indices will include large IPOs after 10 trading days, provided they meet specific full market cap and float-adjusted market cap thresholds (e.g., ~$26 billion and ~$13 billion for the US market, respectively). SpaceX meets these criteria.

FTSE Russell [11:01]

FTSE Russell also adapted its rules in February.

• Fast Entry Rule: A fast entry rule was introduced for top 500-sized securities to ensure better market representation.
• Inclusion Criteria: Eligible IPOs will be added after the close of the fifth trading day following their initial listing, provided they meet the minimum size requirement for the FTSE Russell US equity indices (i.e., being a top 500 company by market cap at IPO).
• Low Float Exception: Companies with less than a 5% free float can still qualify if their lockups are scheduled to expire within 12 months, raising the float above the minimum. SpaceX is expected to satisfy this criterion due to its early lockup release plan.

S&P 500 & Total Market Index [11:56]

S&P took a divergent path from other index providers for its flagship S&P 500 index.

• S&P 500's Decision: S&P rejected all proposed changes for the S&P 500, which included:
  • Reducing the IPO seasoning period from one year to six months.
  • Waiving the investable weight factor (float issue) for mega-cap companies.
  • Including a financial viability exception (allowing inclusion without net positive income) for mega-cap companies.
• Implications for S&P 500: Consequently, SpaceX will not be eligible for inclusion in the S&P 500 until at least mid-2027, and only if it achieves profitability by then. This decision means a significant portion of indexed assets will not automatically acquire SpaceX shares.
  • This could lead to performance divergence between the S&P 500 and other US stock market indices that do include SpaceX.
• S&P Total Market Index: In contrast, the S&P Total Market Index, which tracks a broader universe of US stocks, already had fast-track inclusion and adopted changes to eliminate the 10% free float requirement for top 100 companies by total market cap. Therefore, SpaceX is expected to be included in this index.

Retail Access to SpaceX [14:21]

SpaceX's IPO is distinct due to its aggressive pursuit of retail investor participation.

• High Retail Allocation: SpaceX aims to allocate 30% of its IPO shares to retail investors, a significant increase from the typical 5-10% seen in other IPOs.
• Fixed IPO Price: The company is reportedly setting its IPO price in advance, rather than using traditional book-building methods.
• Elon Musk's Influence: This strategy leverages Elon Musk's strong relationship with retail investors who often invest based on his vision.
• Lowered Entry Barriers: Brokers like Fidelity have drastically reduced their minimum investment requirements for retail investors to participate in the SpaceX IPO (e.g., from $100,000 to $2,000). Other discount brokers are also promoting access.
• IPO "Pop" and Anti-Flipping Rules: Historically, buying at the IPO price has often led to an "IPO pop" – a significant price jump from the offering price. However, many brokers enforce anti-flipping rules, requiring investors to hold shares for a certain period (e.g., 90 days for Wealth Simple, 15 days for Fidelity) to retain access to future IPOs.

  

Retail IPO Access: The Data [15:57]

Recent research casts doubt on the benefits of increased retail investor access to IPOs.

• "Retail IPO access: High hopes, low returns" Paper [2025]: A study analyzing 24 IPOs that included retail investor allotments through platforms like Robinhood and SoFi (both involved in the SpaceX IPO's retail distribution) found concerning trends.
• Underperformance: On average, these retail IPO stocks declined by over 60% from their offer price after one year, underperforming regular non-retail IPOs by 20 percentage points during the same period.

  

• Explanations for Underperformance:
  • Adverse Selection: Issuers and underwriters appear to prioritize aggressively priced deals for retail IPOs, where less informed retail investors are more likely to receive larger allocations of what turn out to be less favorable investments. This creates a "winner's curse."
  • Attention-Driven Trading: Brokers promote upcoming IPOs via notifications and emails, leading to a sharp spike in retail investor interest and Google searches prior to trading. This surge in attention and buying frenzy temporarily inflates prices. As attention fades and buying pressure dissipates, prices tend to fall.
  • The study found that controlling for first-day retail trading volume made the underperformance gap statistically insignificant, suggesting that this attention mechanism is a major factor in the poor post-IPO performance of these stocks.

    

What This Means For You [18:44]

The combined impact of index rule changes and the unique retail allocation strategy for SpaceX has several implications for investors.

• Index Fund Exposure: Most major stock indices (excluding the S&P 500) will likely include SpaceX shares within days or weeks of the IPO.
  • Index funds are mandated to track their respective indices, so if you hold a broad market index fund, you will automatically own a small piece of SpaceX.
  • However, given the low free float and float-weighted methodologies of most indices, SpaceX's allocation will likely be very small (e.g., 0.05% of a Vanguard All-Equity ETF like VEQT).
• Retail Investor Caution: Direct investment in the SpaceX IPO for retail investors warrants caution.
  • While Elon Musk's fan base has a history of supporting his companies, the historical data on retail IPO access suggests a potentially "bumpy ride" with significant underperformance in the year following the IPO due to adverse selection and attention-driven trading.
  • The speaker does not predict a price drop but advises prudence for individual retail investors considering direct participation.
• The "Active" Nature of Indexing: The rule changes by various index providers underscore that indexing is not as purely "passive" as commonly perceived, as active decisions are made in how indices represent the market.
  • Some actively managed funds, like those from Dimensional Fund Advisers and Avantis, offer the benefits of low fees and broad diversification while retaining the discretion to selectively invest in IPOs, potentially avoiding the pitfalls of mechanical index inclusion.