SpaceX and OpenAI: The Mega IPO Grift

Key Concepts

• Mega IPOs: Initial Public Offerings of massive private companies (e.g., SpaceX, OpenAI, Anthropic).
• Index Inclusion: The process by which an index (like the S&P 500) adds a new stock, forcing index funds to purchase shares.
• Fast-Track Entry: Rules allowing new IPOs to be added to indices within days rather than months.
• Free Float: The portion of a company’s shares available for public trading.
• The New Issues Puzzle: The empirical observation that IPOs consistently underperform the broader market over the long term.
• Shadow Tax: The cost borne by index fund investors when they are "front-run" by hedge funds during index rebalancing.
• Adverse Selection: The tendency for index funds to buy overvalued stocks at the moment of IPO because they lack the discretion to avoid them.

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1. The Mechanics of Index Inclusion and "Shadow Tax"

Index funds are designed to track the market, which necessitates including new IPOs. However, this creates a structural disadvantage:

• Forced Buying: When an index adds a stock, funds tracking that index must buy it regardless of price. This provides liquidity to insiders and early investors, often at the expense of index fund holders.
• Fast-Track Entry: Indices like the CRSP US Total Market Index allow inclusion within 5 days. Research shows that "fast-track" IPOs outperform non-fast-track ones leading up to the inclusion date, only to revert significantly within two weeks.
• The Shadow Tax: Hedge funds and intermediaries anticipate index fund demand and "front-run" the purchase. Index funds end up buying at the peak, effectively paying a "shadow tax" as the stock price reverts to its fundamental value.

2. The Problem with Low-Float IPOs

Companies like SpaceX are expected to have "low floats" (e.g., less than 5% of equity available to the public).

• Volatility: Low supply relative to high demand creates extreme price swings.
• Index Weighting: Indices are currently debating how to handle these. Nasdaq has proposed rule changes to include low-float stocks using a "float factor," which critics argue is a move to attract high-profile listings at the expense of index fund investors.
• Historical Data: Professor Jay Ritter’s research on 11 large, low-float IPOs (under 5% float) found that 10 underperformed the market within three years, with average underperformance exceeding 60% from the first-day close.

3. The "New Issues Puzzle" and IPO Underperformance

Empirical evidence consistently shows that IPOs are poor long-term investments:

• Historical Performance: A 1995 study found IPOs returned 5% annually compared to 12% for established firms. A 2019 Dimensional Fund Advisors study confirmed that IPOs underperform the market by ~2% per year.
• Factor Characteristics: IPOs typically exhibit traits of "junk" stocks: small-cap, high-growth, low-profitability, and aggressive asset growth.
• The Renaissance IPO ETF: This fund, which tracks large US IPOs, has underperformed the total market (VTI) by over 6% annualized since 2013.

4. Market Timing and Portfolio Drag

Index funds are forced to engage in "bad market timing."

• Issuance Bias: Companies go public when they believe their valuation is at a peak.
• Performance Drag: A 2025 paper estimates that the mechanical rebalancing of indices to include new, high-priced IPOs creates a performance drag of 47 to 70 basis points per year compared to a strategy that delays rebalancing.

5. The Myth of Private Market Access

Investors often seek exposure to private companies before they go public, but this is fraught with risks:

• Survivorship Bias: For every success like SpaceX, thousands of companies fail.
• High Costs: Special Purpose Vehicles (SPVs) often charge exorbitant fees (e.g., 4% upfront + 25% of profits).
• Liquidity Issues: ETFs attempting to gain private exposure (like the XOVR ETF) have struggled with liquidity and underperformed the market, proving that intermediaries rarely offer retail investors "free" value.

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Synthesis and Conclusion

The upcoming wave of mega IPOs highlights a fundamental flaw in rigid index-tracking strategies. Because index funds are mandated to track the market, they are structurally forced to buy overvalued IPOs, often at the peak of their "first-day pop." This results in a consistent performance drag.

Actionable Takeaways:

• Accept the Cost: If you remain in traditional index funds, recognize that paying this "shadow tax" is part of the cost of the indexing lifestyle.
• Consider Alternatives: Investors may look toward funds (such as those from Dimensional Fund Advisors) that are broadly diversified but utilize "discretionary" rules to avoid IPOs for a set period (e.g., one year) and tilt away from low-profitability, high-growth "junk" stocks.
• Avoid Private Market Hype: Retail attempts to access private equity via SPVs or crossover ETFs are generally inefficient and expensive, often resulting in lower returns than the public market.