Brian Posner

Brian Posner has more than 35 years of experience as a senior corporate executive, strategic advisor, investment professional, and board director across public, private, and not-for-profit organizations.

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Brian currently serves as a director of Arch Capital Group (ACGL), where he chairs the Finance, Investment, and Risk Committee. Previously, he served as Chair of Bioverativ (BIVV) and the AQR Funds, and as a director for Biogen (BIIB), Sotheby’s (BID), and The Mutual Fund Store (a private company), among others.

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His leadership experience includes serving as President and CEO of ClearBridge Advisors, a $100+ billion asset management firm. Prior to that, he was Managing Member of Hygrove Partners LLC, a value-based equity hedge fund group; Managing Director and co-Chief Investment Officer at Warburg Pincus Asset Management; and Vice President and Portfolio Manager at Fidelity Investments, where he was sole manager of a nationally recognized, top-performing equity mutual fund.

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Brian is deeply engaged in academia and governance. He is a Charter Trustee at Northwestern University and an advisor to Northwestern’s Center for the Study of Diversity and Democracy. Additionally, he is an emeritus member of the Board of Visitors at Northwestern’s Weinberg College of Arts and Sciences, where he previously served as co-Chair.

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Recognized as an expert in corporate strategy, governance, financial analysis, and investing, Brian is frequently invited to guest lecture at institutions such as Columbia University’s Graduate School of Journalism and Northwestern’s Kellogg School of Management.