iShares is a collection of exchange-traded funds (ETFs) managed by BlackRock, which acquired the brand and business from Barclays in 2009. The first iShares ETFs were known as World Equity Benchmark Shares (WEBS) but have since been rebranded.Most iShares funds track a bond or stock market index, although some are actively managed. Stock exchanges listing iShares funds include the London Stock Exchange, American Stock Exchange, New York Stock Exchange, BATS Exchange, Hong Kong Stock Exchange, Mexican Stock Exchange, Toronto Stock Exchange, Australian Securities Exchange, B³ Brasil Bolsa Balcão and a number of European and Asian stock exchanges. iShares is the largest issuer of ETFs in the US and globally.