Marc is a partner in the Washington, DC, office of the law firm, Loeb & Loeb, LLP, where he specializes in federal tax issues relating to tax-exempt organizations, including charities and issue advocacy groups. Prior to joining Loeb & Loeb, he spent 15 years in private practice and 25 years with the US Internal Revenue Service, including serving as Director of the Exempt Organizations Division from 1990 until 2000. As Director of the Exempt Organizations Division, he was responsible for the design and implementation of federal tax rulings and enforcement programs for charities and other tax-exempt organizations. He is a member of the District of Columbia and Florida Bars and he is a member of the Board of Directors of the Pemsel Case Foundation, a Canadian foundation focusing on the development of the law of charity. He is also co-chair of the Subcommittee on Audits and Appeals of the Exempt Organizations Committee of the American Bar Association Tax Section. Chambers USA ranked him as a “Top Lawyer” in 2009-2012; he is also named to “Best Lawyers of America” for Nonprofit/Charities Law and Tax Law for 2008-2018. Thomson Reuters identified him as a “Washington, DC Super Lawyer” in 2012-2017; and The Legal 500 US named him as a “Leading Lawyer” in Nonprofit and Tax Exempt Organizations.