The life cycle of a share starts at IPO. The S&P 500 does not add companies to its index until at least 12 months after IPO.

Also, Meta issued 180 MM new shares at $38/share at IPO. That’s ~$7 Bn. Which is less than 1/4th of what they repurchased just last year.

Between share repurchases and dividends, S&P 500 companies are putting money into the markets, not pulling it out.