Mega-IPOs from SpaceX and others could intensify already 'dangerous' concentration risk in the stock market

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• Nearly 40% of the S&P 500's weight is made up of its 10 largest stocks.
• If SpaceX, OpenAI, and Anthropic go public, that weighting could jump to 50%.
• While top-heavy market concentration isn't inherently bad, experts warn it can intensify risks.

Just 10 stocks account for nearly 40% of the S&P 500's value, the highest concentration in the stock market since the Great Depression.

What's more, if SpaceX, OpenAI...