In a move that could disrupt some types of betting on the Finals, the NBA plans to cut off unauthorized sportsbooks from accessing the league's official data feed starting next week.

Sportradar, an authorized data distributor for the NBA, sent a letter Thursday notifying sportsbook operators that the league was forcing it to "cease providing to you NBA Official Data for use in the United States unless and until you are an Authorized Gaming Operator of the NBA."

According to the letter, obtained by ESPN, Sportradar will shut down access of the feed at 11:59 p.m. ET on Tuesday. Game 1 of the Finals is Thursday.

The NBA has partnered with three sportsbook operators: MGM, FanDuel and The Stars Group. As official league gaming partners, those bookmaking companies have access to the official data feed.

NBA head of fantasy and gaming Scott Kaufman-Ross told ESPN on Friday that sportsbooks were aware that a season-long grace period for use of the data was coming to an end, adding that the league will continue to discuss additional partnerships.

Sportradar did not immediately respond to a request for comment from ESPN.

Last May, the U.S. Supreme Court struck down the Professional and Amateur Sports Protection Act of 1992, the federal statute that had restricted state-sponsored sports betting to primarily Nevada. Since the ruling, legal, full-scale sportsbooks have opened in Delaware, Mississippi, New Jersey, New Mexico, Pennsylvania, Rhode Island and West Virginia, and several more states plan to enter the bookmaking business at some point this year.

The NBA's data feed is primarily used by sportsbooks to run their live betting options, updating odds that are offered on different outcomes throughout the game. Live or in-game betting is a growing market in the U.S. but still does not represent significant betting handle for sportsbooks in Las Vegas. The vast majority of money bet on in-game wagering options is on the point spread, money-line and over/under total points, bookmakers say.

The Las Vegas sportsbook operators that have not signed deals with the NBA are mulling their options, including manually producing the live odds or simply stopping live wagering on the NBA altogether.