J.F. Lehman & Company, a middle-market investor focused on the defense, aerospace and maritime sectors, has made four promotions. Lisa M. Steffens has been named managing director, Fund Finance and Investor Relations. She joined the firm in 2006 and served for six years as the firm's director of Investor Relations. David L. Rattner has been named managing director, Legal, Administration and Compliance. Mr. Rattner joined in 2011 as general counsel. William J. Hanenberg has been promoted to vice president. He joined the firm in 2008 after serving as an investment banking analyst with Banc of America Securities. David F. Thomas has been promoted to senior associate. He joined the firm in 2010 after serving as an investment banking analyst in Credit Suisse's Mergers and Acquisitions Group.