Stephen Martino, lottery director, signed the license for the casino, owned by the Baltimore-based Cordish Cos., lottery officials said.
Martino said that the $500 million facility at Arundel Mills mall was safe and that gaming was being conducted fairly.
On Saturday, 7,500 people attended a trial run of the casino. The controlled demonstration tested the slot machines, food and beverage services, internal controls, employee training, surveillance and security, and technical systems, according to the Maryland Lottery.
The slots facility will donate its portion of the proceeds from the event to the Anne Arundel Medical Center Foundation, Baltimore Washington Medical Center Foundation, Anne Arundel Community College Foundation and the Baltimore Area Council of the Boy Scouts of America, the Lottery said.
The casino and its ancillary developments will employ 1,500 when complete. Maryland Live will be the third casino to open in the state.
The others are Hollywood Casino Perryville, which opened in September 2010, and the Casino at Ocean Downs, which began operations in January 2011. To date, the casinos have generated $227.6 million in total gaming revenue, with more than $110 million going to Maryland's Education Trust Fund.