Martin Richards, the longtime Broadway producer known to legiters as Marty, died of natural causes in his Manhattan home on Monday. He was 80 and had been battling cancer in recent months.Richards had an impressive string of stage producing credits including the original productions of “Sweeney Todd,” “La Cage aux Folles,” “On the Twentieth Century,” “Chicago,” “Grand Hotel” and “The Will Rogers Follies,” as well as Off Broadway success “March of the Falsettos.” He also produced a small batch of films, having a hand in notable titles “The Boys From Brazil” and “The Shining.” He was also a producer of the Oscar-winning 2002 film version of “Chicago.” He sued Miramax in 2006 claiming an unpaid share of the film’s revenue; the case was settled two years later. Richards was head of legit and film production company the Producer Circle Co., which he founded in 1976 with his late wife Mary Lea Johnson. His stage resume also included the 1981 Broadway production of “Crime of the Heart” as well as 2002 musical “Sweet Smell of Success,” the 2004 revival of “La Cage aux Folles” and 2005 outing “Chita Rivera: A Dancer’s Life.” His most recent project, musical “Big Maybelle: Soul of the Blues,” bowed at Long Island’s Bay Street Theater over the summer. Plans for a future life for the show remain up in the air. Richards was also a philanthropist who played major roles in Broadway Cares/Equity Fights AIDS and Meals on Wheels, and he established a liver and kidney transplant unit, named after his wife, at the New York U. Medical Center. He also founded the New York Center for Children for abused children and their families. Richards was born in the Bronx. He’s survived by brother Bruce Klein as well as a niece and a nephew. Funeral will be held at the Frank Campbell Funeral Chapel in Manhattan, with visitation hours Nov. 28 and Nov. 29.