SEPTEMBER 24, 2026, CHICAGO – The firm is pleased to announce that Mark S. Perwien has joined the firm as Of Counsel, continuing his illustrious career in private practice after his work in government and on Wall Street.

Perwien has focused on the overlap of taxation and derivatives law for more than 40 years. He began his career at Salomon Brothers, remaining with that firm and its successors for 20 years through various management roles to ultimately assume tax department leadership at Citigroup. Perwien left Citi to assume similar high-level roles at Goldman Sachs where he led activities at the derivatives desk and the tax department. Perwien went on to join the Internal Revenue Service (IRS) where he served as Special Counsel, Office of the Associate Chief Counsel, Financial Institutions and Products in Washington; and as Senior Advisor, Financial Products, to the Director of Enterprise Activities, Large Business and International Division in New York for more than a decade.

“ASKramer Law addresses some of the most complex and challenging tax and regulatory questions in financial law today. My focus has always been to consider these questions in practical ways that comply with the law, and withstand scrutiny in this fast-changing regulatory landscape,” Perwien said. “Today, digital asset market innovators are reshaping brokerage, banking, and exchange operations as we know them, so it is an exciting time to be working in the world of derivatives. An association with Andie’s firm offers a compelling opportunity to continue to focus on work that I enjoy, and to team with someone I hold in the very highest regard.”

In his roles at Treasury and IRS, Perwien served as the ultimate technical reviewer for complex cases and in drafting rules with respect to the taxation of financial products. He has contributed directly to IRS and Treasury statutory interpretations on business hedging, mark-to-market accounting, and original issue discount reporting with major implications for the securities and commodities markets.

“Our clients expect an exceptional depth of knowledge in financial product regulation and taxation, and Mark brings an extensive record of achievements in this regard,” said Andie Kramer, founding member of ASKramer Law. “Throughout our long-standing relationship, Mark and I have regularly collaborated on important projects, and continued collegial associations during his IRS tenure. Now, it is my great honor to finally name Mark as a colleague at this firm. Without doubt, Mark is a superb fit for the needs of our clients, and his excellent grasp of both domestic and international issues only strengthens our bench as a boutique derivatives and tax law firm.”

Perwien is based in New York City, New York. He and his wife are philanthropists, including their significant commitments and support for developmentally disabled people. We are delighted to welcome Mark to the firm.

About ASKramer Law

ASKramer Law is a boutique Chicago law firm established in 2023 to assist clients with the management of complex legal risks and board-level decisions. The firm provides integrated legal counsel on regulatory, governance, commercial, and tax matters, delivering incisive advice to finance and energy clients on US financial products law. For more information, please reach out to us at www.askramerlaw.com/contact.

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