Robert F. Maguire III (Getty) Prolific Los Angeles developer Robert F. Maguire III died Tuesday at his home in Studio City. Maguire was 86 and died of complications from pneumonia, according to the L.A. Times. His most prominent project was the U.S. Bank Tower, the tallest building in L.A. from 1986 to 2010. The 73-story Downtown tower sold to Silverstein Properties last July for $430 million. Maguire was born in Portland, Oregon, in 1935 and relocated to L.A. to study at UCLA, where he graduated in 1960. He got his feet wet in real estate at Security Pacific National Bank and started his own firm in 1965.