Exchange traded funds (ETFs) are popular with investors, but not with the managers who run them. Filings show most fund managers at some of the biggest ETF providers don’t put their own money into the funds they run.  "It has been easier to know this thanks to a rule by the SEC that requires fund companies to disclose whether fund managers hold stakes in funds they run," written in WSJ online. Fund watchers have argued that investors benefit if the interests of the managers align with those of the shareholders.

An ETF passively tracks a market index and is not actively managed.  The manager does not have the same control on returns for the ETF as it would if they were picking the stocks themselves.  Providers say there are different measures to look at, such as how closely the manager tracks the index.