The tactic, in some ways, resembles illegal front-running – – but in this case, it’s perfectly fine. The traders are simply buying stocks before they’re added to the indexes that, by definition, index funds must track.
As the popularity of index investing soars to new heights, the emergence of index front-running is raising fundamental questions about so-called passive investment strategies, as well as how indexes are compiled and the role the funds themselves play in elevating costs. By one estimate, it gouges owners of funds tracking the Standard & Poor’s 500 Index to the tune of $4.3 billion a year, a sum that can double or even triple the cost of such investments.
“Portfolio managers are aware of it, but some of them will say ‘My clients demand an index fund, and I’m going to give it to them come hell or high water,’” Michael Rawson, an analyst at Morningstar Inc., said from Chicago. “Yes, you matched the index return, but the investor is now worse off. You don’t hear about that as much.”