A dispute between the simulcast-marketing arms of The Stronach Group and Churchill Downs Inc. has led to a blackout at some wagering sites of the signal from Pimlico Race Course, where the second leg of the Triple Crown, the Preakness Stakes, will be run on Saturday. The dispute is so far affecting customers of BetAmerica, a small account-wagering company owned by Churchill, plus the racetracks Presque Isle Downs in Pennsylvania and Louisiana Downs. Churchill closed a deal to buy Presque Isle early this year, while Louisiana Downs recently signed on with Churchill to market its simulcast signal. While shut-out customers have options to bet the Preakness by opening accounts with wagering sites that have access to the signal, the dispute underlines the consequences of the consolidation of simulcast-marketing power under the Churchill and TSG brands. Some sites were shut out several weeks ago from offering wagering on the Kentucky Derby due to a similar dispute. The Stronach Group owns Pimlico Race Course, and it buys and sells a slew of simulcast signals under an arm of the company called Monarch Content Management. Churchill Downs markets its own signals, and it has recently been signing on tracks that are otherwise unassociated with the company in order to increase its leverage in the simulcast marketplace, in part as a counterweight to Monarch. Officials for both Monarch and Churchill Downs on Friday declined to provide specifics as to what is underlying the dispute. Both said that negotiations were continuing on the affected sites up until Thursday night, and that it is possible the sides could resolve the impasse prior to the Preakness. In a statement, Churchill Downs noted that the dispute has shut out the affected customers from the signals of all of the tracks represented by TSG, including Santa Anita and Gulfstream Park. The statement claimed that the dispute escalated into an impasse after TSG requested that CDI allow some "additional" computer-assisted wagering customers from TSG's high-rollers rebate shop into CDI's pools, a request that CDI rejected. “We’re disappointed and frustrated by their unnecessary tactics, which were unreasonable and intentional last-minute demands in an attempt to leverage the Preakness Stakes,” the statement said. BetAmerica is a much smaller account-wagering company than Churchill’s flagship twinspires.com, the leading account-wagering company in the U.S. Churchill bought the company in 2017, and it recently re-launched the site as its sports-wagering operation for jurisdictions that have legalized on-line sports betting. Although Louisiana Downs and Presque Isle Downs came under Churchill’s umbrella many months earlier, the dispute did not begin to affect those companies until they recently opened their live racing meets.