Index funds have grown at tremendous pace, now totaling over $6 trillion and representing more than 17% of total stock market value.  Including actively managed funds, mutual fund managers represent more than 35% of the shares of U.S. corporations - and the trend indicates this will grow to 50% or more.  John Bogle discusses the emerging issue, and potential ways to mitigate the risk of corporate voting being controlled by a small number of individuals.