Mark H. Leeds is a Tax Transactions & Planning partner in Mayer Brown's New York office. His practice is focused on the tax consequences of a variety of capital markets, hedge fund, banking and insurance products and strategies, including over-the-counter derivative transactions, swaps, tax-exempt derivatives and strategies for efficient utilization of tax attributes—such as net operating losses. Mark regularly works on innovative insurance products and structures. Mark has extensive experience in working with businesses and individuals seeking to set up operations and relocating to Puerto Rico. Mark advises on the tax aspects of capital markets, structured finance, derivatives, financial products and insurance transactions and has extensive experience working with both buyers and sellers to develop and structure complex derivatives, including litigation finance transactions. A significant portion of his work involves the taxation of financial products and trading strategies engaged in by banks and other financial market participants. He also advises on hedge fund and other investment vehicle formation matters. Mark does extensive work with digital assets, including cryptocurrencies, non-fungible tokens and blockchain transactions. Mark is a former managing director and senior tax counselor with Deutsche Bank in New York. He also served as the general counsel of a credit derivative company and was a partner at Deloitte & Touche, where he led the capital markets tax practice. Mark is a frequent writer and speaker on tax topics affecting capital markets and digital assets.

Daniel Hemel joined the New York University School of Law in June 2022 as a Professor of Law. His wide-ranging research explores topics in taxation, intellectual property, administrative and constitutional law, and nonprofit organizations. He has published more than fifty scholarly articles and essays in law reviews and economics journals, including in the Columbia Law Review, NYU Law Review, Stanford Law Review, University of Chicago Law Review, Yale Law Journal, Journal of Economic Perspectives, and National Tax Journal. His academic work has been cited by the U.S. Supreme Court, multiple federal courts of appeals, and the Presidential Commission on the Supreme Court of the United States. In addition to his scholarly writing, Hemel has published dozens of essays and op-eds on tax policy, constitutional law, and current events in leading national newspapers, including the New York Times, Wall Street Journal, and Washington Post. He has testified before Congress and the California State Assembly on tax topics, and he has assisted U.S. senators, House members, and state lawmakers in drafting tax legislation. He is a co-editor of the Journal of Legal Analysis, and he serves on the Board of Directors of the National Tax Association and the Environmental Law Institute.