Neil Goulden, Gala chief executive, said: "Casinos like Leo rarely become available, so we are particularly pleased to be able to bring it into the Gala Group.
"I believe we are now well-placed to develop the business by adding operational, management, marketing and cost-effective promotional skills to an already successful operation.
"Today's acquisition demonstrates our confidence in Gala's casino brand and this is a terrific opportunity for Gala to expand its operations in the Merseyside area." Mr Taittinger, part of the champagne family with the same name and who named his casino after his pet dog, first invested in land and hotels at Queens Dock in the late 1980s.
He said: "I feel extremely proud that Gala is to become the new operator of the Leo Casino in Liverpool. Gala, with over 30
casinos in their estate, have an excellent reputation as market leaders in the industry. I am confident that the already successful Leo Casino will progress with Gala Group's experience to the benefit of the customers, employees and Liverpool in general.
"I wish all the best for the future of Leo and personally remain committed to Liverpool with the ownership of the Dolby Hotel."
As well as casinos, Gala operates 175 bingo clubs, 1,267 licensed betting offices and with an online gaming business.