Antti Petjusto, a money manager at BlackRock, has argued that the estimated indirect impact could raise the actual expense of an index fund by 28 basis points. To put this in perspective, VOO has a 0.05% expense ratio, IVV has a 0.07% expense ratio and SPY has a 0.09% expense ratio.

Nevertheless, some fund providers are trying to mitigate the risk of front running. For instance, Vanguard Group tries to gradually build up positions over time if stocks are scheduled to be added, according to Doug Yones, Vanguard’s head of domestic equity indexing and ETF product management.

“It just comes down to being smart with your trades,” Yones said in the article. “It’s a big enough deal that index managers are aware and spend time and energy making sure there isn’t an impact.”

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Max Chen contributed to this article.

Full disclosure: Tom Lydon’s clients own shares of IVV and SPY.