Mark Lawrence Epstein (born July 14, 1954), nicknamed "Puggy",[1] is an American property developer, and the brother of convicted sex offender and financier Jeffrey Epstein. A former artist, Epstein has been a real estate investor since the 1990s. He was the president of his brother's investment company, J. Epstein & Co, and an executive of Ossa Properties. He founded and led real estate companies, a T-shirt printing business, a modeling agency, and a charter company.[2] His wealth and its source have been the subject of investigation by both Dow Jones Institutional News and The Wall Street Journal.