John Siena

John Siena

Managing Director
London | England

John Siena

John Siena is Associate General Counsel and Co-Head of Regulatory Strategy at BBH. Until recently, John ran BBH’s Asia legal function. He has a particular interest in how financial services develop in a challenging world and how policy-makers, governments, and regulatory authorities interact with industry to provide for safer and more efficient capital markets that foster growth, sustainability, and availability of opportunity for all investors.

John originally joined the firm in 2005, as Director of Legal Operations, EMEA. John re-joined BBH in 2014 from Bank of New York Mellon where he had held the role of Head of External and Regulatory Affairs, EMEA.

Before joining BBH, he held roles at Northern Trust as Senior Legal Counsel for investment management business lines and Senior Attorney for custody and investment management businesses lines.

John participates actively in many industry groups, including the Association of Financial Markets in Europe (AFME), where he previously chaired the Legal Committee (Post-Trade), the International Securities Services Association (ISSA) and The Association of Global Custodians (AGC), for which he currently chairs the European Committee.

John has written and contributed to many position papers and submissions on developing legislation, mostly in Europe. Recent publications include contributions to The Alternative Investment Fund Managers Directive, 3rd Edition (edited by Dirk Zetzsche) (Kluwer Law International, 2020), and the forthcoming Financial Collateral (edited by Matthias Haentjens) (Oxford University Press).

John graduated from the University of Illinois at Urbana-Champaign with a B.A in European history and the University of Virginia School of Law.

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