Twinspires.com, the account-wagering operation owned by Churchill Downs Inc., retained its ability to take wagers from California residents after notifying state regulators on Friday that it had reached an agreement with California racetracks to carry their signals, officials for the company and the California Horse Racing Board said. At a meeting on Monday, the board approved a resolution renewing Twinspires.com’s license but attached a caveat requiring the agreement by Friday, or the license would be rescinded. The California racing board said in a statement that the license for Twinspires.com “remained in full effect” on Friday after the agreement was reached. Twinspires.com is the largest account-wagering operation in the United States, and California is the country’s largest single jurisdiction. The inability to take bets from California residents would have had a significant impact on the company’s business. Twinspires.com was required to reach an agreement with Monarch Content Management Services, a company formed late last year that sells the rights to the signals from tracks in California and other states. Scott Daruty, the chief executive of Monarch, said on Friday that the contract with Twinspires.com runs through early December.