ETFs' Low-Cost Shell Game

Last week, industry giant BlackRock doubled the size of its new, low-cost "core" ETF lineup, with steep expense-ratio cuts on several iShares ETFs. But there's more to that move than just cheaper funds for individual investors. It used to be that only the simplest, broadest ETFs were fee battlegrounds, because that's where the price-conscious individual investor is. Except BlackRock didn't chop expense ratios on its biggest and most successful ETFs; it just cut fees on rechristened small funds and new launches. So its biggest ETFs escape fee pressure, while new -- and often remarkably similar -- offerings compete on price.