BlackRock remains the largest ETF provider, surpassing $3 trillion in assets under management, about one-third of the industry’s $9.4 trillion worldwide AUM. Vanguard, with about $2 trillion AUM, offers the other major ETF family. The drop off after those two is significant, with State Street in third place — with more than $800 million in AUM — followed by Invesco’s roughly $400 million.