Vanguard is in the business of selling index funds. It's Vanguard's incentive for mutual funds and hedge funds to face unnecessary taxes on their trades. This l

Vanguard is in the business of selling index funds. It's Vanguard's incentive for mutual funds and hedge funds to face unnecessary taxes on their trades. This lowers the returns of active investing versus passive investing. What's bad for everyone else is good for Vanguard. It's true that IEX is a dark pool, and that other dark pools exist that purport to favor natural traders, but IEX is moving toward an ECN and full-fledged exchange in a staged launch. Other dark pools are highly conflicted, lack transparency, lack technical protections, and the biggest difference is that people seem to trust the principals of IEX and the incentives of the ownership structure.