Which is a dumb idea, of course, as that just leaves the control over your capital to your adversaries. Passive investing works because goals are aligned: The only way to influence an index fund on the investing side of things into doing something stupid is by doing something stupid yourself. If you want to make an S&P500 index fund buy some penny stock, you have to buy it yourself first in massive quantities paying massive prices for it to drive up the market cap. Voting does not work that way.