On Leaks in the Daily Fantasy Sports World

Ownership percentage is one piece of the puzzle that can be useful in skillfully setting DFS lineups, especially in guaranteed prize pool contests. Top players try to predict ownership percentages, and data about past ownership percentages can be dissected for information.

— Chris Grove, DraftKings Lineup Leak Rocks Daily Fantasy Sports Industry: Questions And Answers

I’ve long wondered how these sort of leagues can do what they do, given that sports betting isn’t legal in these United States. Data leaks like this won’t help the cause either; the commnetary I’ve read suggests this is something akin to insider trading, even though it appears no advantage was gained.