The Las Vegas-based casino company reached a deal in July with Vornado Realty Trust and Geyser Holdings to sell just over 11 acres and ground leases on the land on which part of the Borgata sits.
It's part of the company's phased exit from the nation's second-largest gambling market.
MGM is selling its half ownership in the Borgata, Atlantic City's top casino, to an unnamed bidder for more than $250 million.
The company acted after an ultimatum from New Jersey casino regulators that it sell its 50 percent stake in Atlantic City's top casino, or cut ties with Pansy Ho, its partner in a casino in the Chinese enclave of Macau.
Ho's father, Stanley Ho, has long been accused of ties to Chinese organized crime, which he denies. MGM chose to keep its relationship with Ho and walk away from the Borgata.
Considered the father of modern gambling in China, Ho lets criminal gangs "operate and thrive" inside his casinos, the New Jersey Division of Gaming Enforcement said in a report issued to the casino in May 2009 and made public in March. The division found that Pansy Ho, his daughter, is dependent on him and his money and remains under his influence.
The regulators concluded that Pansy Ho is an "unsuitable" business partner of MGM in Macau. The company admits no wrongdoing and says it has a "spotless record" operating the MGM Grand Macau with Pansy Ho.