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COLUMBUS, Ohio (WCMH) — Less than a week into legalized sports gambling in Ohio, three more online proprietors received violation notices Thursday for their advertising, the Ohio Casino Control Commission said.

The commission sent notices to the licensed services providers of BetMGM, Caesars, and DraftKings — or their affiliate marketers — alleging all three advertised across platforms without visible mandatory problem gambling messaging that is required under state law and the commission’s rules and regulations, according to a press release.

The string of violation notices came after the commission already issued two notices to the parent companies of the DraftKings and Barstool sportsbooks before Sunday, the state’s universal start date for betting. Both stared down a possible fine in the hundreds of thousands of dollars for advertising that the commission said directly targeted people under 21.

Ohio Gov. Mike DeWine foreshadowed growing concern at a press conference Wednesday, saying proprietors “need to be aware that they’re being looked at very closely by the governor and the Casino Control Commission.”

Online gambling through digitized sportsbooks will reign supreme for most Ohio bettors, according to Matt Schuler, executive director of the Ohio Casino Control Commission. When it comes to regulation and enforcement of them, Schuler characterized it as “a new frontier” in an earlier interview with NBC4.

“About 90% of wagers will be placed online. It is going to be the robust part of this market,” Schuler said in an earlier interview. “Part of this is just not going to have eyes on it 24/7.”

All four companies — the three notified Thursday and Barstool parent Penn Entertainment — will be given the choice to either request a hearing or settle the matter directly with the commission, which will vote on the final outcome.

BetMGM, Caesars affiliate American Wagering, Inc., and Crown OH Gaming affiliate DraftKings could all face $150,000 fines.

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