SpaceX and Anthropic (maker of Claude) have filed for IPOs and are nearing public trading. SpaceX is expected to debut in mid-June 2026, while Anthropic aims for as early as October. OpenAI (maker of ChatGPT) is preparing a filing targeting Q4 2026.
Valuations and Market Size Context
These companies carry enormous valuations. SpaceX is targeting approximately $1.75 trillion at $135 per share, which would rank it among the top 5–10 largest U.S. companies by market cap immediately upon listing. Anthropic recently filed at a private valuation near $965 billion, and OpenAI is eyeing $850 billion to over $1 trillion. If achieved, all three could instantly land in the upper half of the S&P 500 and compete for early Nasdaq-100 placement.
Historic Index Inclusion Requirements
Historically, inclusion in major indexes like the S&P 500 required at least 12 months of public trading (“seasoning”), positive GAAP earnings in the most recent quarter and prior four quarters, sufficient market cap, liquidity, and public float. The Nasdaq-100 has introduced “fast entry” rules allowing highly liquid mega-cap IPOs to join in as little as 15 trading days if they rank among the top 40 by market cap.
Timeline for Major Index Inclusion
The S&P Dow Jones Indices Committee has confirmed it will not ease its eligibility rules for now. This means the earliest any of these companies could join the S&P 500 would be roughly mid-2027 (after the required 12-month seasoning period). However, they could join other indexes much sooner, potentially within weeks for the Nasdaq-100 (especially SpaceX) and Russell indexes under their more flexible criteria.
What This Means for Investors
These IPOs could introduce significant volatility and opportunity. Index inclusion typically triggers automatic buying from passive ETFs and mutual funds, often driving substantial inflows.
This environment also underscores a potential advantage of active ETFs and mutual funds. Unlike passive vehicles that must buy shares upon index inclusion (regardless of valuation), active managers can be more selective. They can choose whether, when, and how much to invest based on fundamental analysis, valuation discipline, and risk management. This flexibility may help avoid overpaying for hype while still capturing long-term upside from transformative companies.
While inclusion in major indexes is largely a matter of time, whether these companies will deliver strong long-term returns remains debatable given high valuations, execution risks, competitive pressures, and current profitability challenges.