Billionaire L.A. investor Howard Marks has put his eight-room condo at Manhattan’s Ritz-Carlton on the market, with a listing price of $50 million.

Marks, the chairman and co-founder of downtown Los Angeles private equity firm Oaktree Capital Group LLC, reportedly is asking more than more than double what he paid for it in 2007. His real estate agent at Sotheby’s International Realty told Bloomberg News that Marks and his wife have made significant improvements to the 4,500-square-foot apartment over the years.

The two-bedroom, four-bath apartment on New York City’s Central Park South is one of only 12 residences above the iconic Ritz-Carlton hotel. The unit went on the market on July 7, according to StreetEasy.com and Sotheby’s International Realty websites. Marks bought it for $18.9 million five years ago when it was marketed as “raw space.”

Marks, whose primary residence is in Brentwood, ranked No. 31 on the Los Angeles Business Journal’s list of 50 Wealthiest Angelenos in May, with an estimated net worth of $1.35 billion. In May he bought a duplex at 740 Park Avenue for $52.5 million, which Bloomberg says is the highest price ever paid for a New York City co-op.