Is stock market a positive-sum game? As an example, let's say that in an IPO, an investor X buys all the shares, let's say 10, for $10 each (in the primary market). He spent $100, and those $100 went to the company. Next, there appears a bid of 10 shares (now at the secondary market) at $11. The investor X sells all his 10 shares to that bidder Y. Now the investor X has a profit of $10. Now let's say there's a bid for 10 shares at $12. The investor Y sells his 10 shares and made a profit of $10. For this to continue indefinitely there always need to be more money to be invested. If there weren't any other bidder, the shares wouldn't have any value and the last buyer would lose an amount of money equivalent to what the others won, making it a zero-sum game. So is the stock market just an elaborate Ponzi scheme? Or it's a positive-sum game (excluding fees)? Excluding dividends of course.