Yea, I guess the fact that parties value risk differently, gives a little bit of room for positive sum transactions. But, given limited supply (of company shar

Yea, I guess the fact that parties value risk differently, gives a little bit of room for positive sum transactions. But, given limited supply (of company shares) and large transaction volume in equity markets, this effect should be muted. That is, shortly after an IPO, I could see there being truly positive sum transactions as more risk-seeking investors enter the market. But, eventually, risk-aversion between buyer and seller should reach equilibrium and all future transactions will be largely zero-sum.