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Typically, streams can lag from live broadcasts anywhere from eight seconds to a full minute, depending on the company. Live TV broadcasts lag from the live action by around seven seconds. Genius says the lag time at sportsbooks will be about three to seven seconds — a massive edge if you're planning to live bet.
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There are also wager requirements. At Fanatics, you need to bet at least 10 cents on the game you want to watch. At Caesars, the net will be cast far wider — you only need to have placed a wager on an NFL game over the past year.