BlackRock is the largest provider in the world of exchange-traded funds, the passive investing instruments that track indexes rather than relying on managers to pick individual stocks. The firm has $1.17 trillion in ETF assets under management, and its iShares Core S&P 500 (NYSE Arca: IVV) ETF has taken in $17.8 billion in 2017, the most of any passive fund. Its iShares Core MSCI EAFE (NYSE Arca: IEFA) fund, which tracks global equities excluding the U.S., has hauled in just shy of $13 billion, while the iShares Core MSCI Emerging Markets (NYSE Arca: IEMG) fund has seen $11.1 billion in inflows, rounding out the top three this year in the $3 trillion ETF space. More From CNBC