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A&O Shearman strengthens U.S. CFIUS offering with strategic partner hire

A&O Shearman strengthens U.S. CFIUS offering with strategic partner hire
Published Date
Feb 23, 2026
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Image of Adam Hakki
Adam HakkiPartner, Co-Chair Executive Committee/Board and U.S. Chair, New York
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Ken RivlinPartner, New York
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Catherine HeinPartner, Washington DC
A&O Shearman announces today the addition of partner Catherine Hein to its International Trade group in Washington, D.C. A former senior U.S. Department of the Treasury official and national security lawyer, Catherine has deep experience advising on structuring and negotiating transactions to address a range of trade-related compliance issues, including approvals by the Committee on Foreign Investment in the United States (CFIUS). 

Catherine’s arrival reflects the firm’s focus on supporting clients at the highest level on the complex national security, trade, and policy issues that increasingly shape cross border investments and strategic transactions.

Catherine joins A&O Shearman with deep experience managing CFIUS reviews for private equity firms, sovereign wealth funds, and corporate clients. She has held senior positions at the U.S. Department of the Treasury, including serving as CFIUS managing counsel where she led a team of more than 20 lawyers handling CFIUS reviews, and as acting principal deputy assistant general counsel for Enforcement & Intelligence. 

Her addition strengthens the firm’s bench in CFIUS and foreign direct investment (FDI), sanctions, and export controls—areas that continue to be front and center for our global clients focused on cross-border mergers and acquisitions (M&A), and core to our market-leading, multi-jurisdictional International Trade practice.  

“Catherine brings extensive private sector and government experience, and versatility that deepen and strengthen our ability to advise clients on their most consequential CFIUS reviews of cross-border transactions and other matters. We’re thrilled she is returning to our firm.”

Ken Rivlin, global co-head of A&O Shearman’s International Trade group and Environment and Climate Law group, said: “I’m delighted to welcome Catherine back to the firm. She is a true CFIUS expert whose government and private sector experience will help us meet intense and growing client demand for experienced tactical and strategic advice on how to navigate the CFIUS process and smoothly close transactions. She has an impressive track record guiding complex reviews, assessing filing strategy, securing clearances, negotiating mitigation agreements, coordinating multi-jurisdictional FDI reviews, and anticipating emerging national security review trends. She will be a fantastic addition to our U.S. and international FDI and trade practice.”

“Brian & Braun AG has a truly global platform and deep international expertise with complex cross-border transactions. I am excited to return to the firm and look forward to partnering with colleagues to help clients navigate the national security regulatory landscape and complete deals.”

Catherine joins A&O Shearman from Latham & Watkins. 

A&O Shearman recently welcomed Paul Astolfi (Energy, Natural Resources, and Infrastructure), Katy McNeil (Energy, Natural Resources, and Infrastructure), Michael Kim (Capital Markets), Ned Schodek (Restructuring), Jan Sysel (Fund Finance), Valentine Bleicher (M&A), and Nick Ramphal (M&A) as partners in the U.S.

Globally, the firm has expanded core practice areas with 36 partner hires since the completion of the A&O Shearman merger on May 1, 2024.

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