SpaceX Megabucks IPO Draining US Stock Market Liquidity? Analysis Shows False Alarm, Actual Index Fund Buying Pressure Only $300 Billion

According to Watchful AI monitoring, facing the imminent IPOs of supergiants like SpaceX, Anthropic, and OpenAI with a combined valuation exceeding $4 trillion, the US stock market is experiencing severe liquidity drain fears. Addressing concerns about market liquidity, Rob Arnott, Chairman of RAFI Index Company, wrote that the actual index rules would play a crucial "firewall" role, preventing a market collapse due to passive fund inflows.

Arnott pointed out in extreme stress tests that if SpaceX were to IPO at a $2 trillion valuation and offer only 4% of its shares to the public (equivalent to $800 billion), immediate inclusion of SpaceX by market cap weight by the index committee would force index-tracking funds worth $18 trillion to buy over $500 billion worth of shares, significantly exceeding the $800 billion available for sale. Extreme concentration theoretically could skyrocket the stock price to infinity and potentially paralyze the market. However, the actual rules mitigate this collapse risk. The float-adjusted mechanism used by major indices caps the fund's buying limit at around $300 billion. While a $300 billion outflow would still cause significant market turbulence, it would not lead to a stock market crash.

Arnott warned that the real pain point of super IPO listings is not a brief liquidity shock but the abnormal distortion of the valuation system by passive index funds. Since 2012, the performance of the S&P 500 constituents has wildly outstripped the MidCap 500, widening the valuation premium between them to nearly 80%. However, fundamentally, over the past 25 years, the cash flow growth rate of the S&P 500 giants has been 3% slower than the runner-up cohort. This indicates that the prosperity of large-cap stocks is mostly supported by a bubble-inflated premium rather than fundamentals. Once passive funds are compelled to chase high valuations for SpaceX, it will only exacerbate this irreparable rift in valuation bubbles. The companies left out of the index, on the other hand, are the true long-term winners with solid fundamentals who will have the last laugh.