LAWYER PROFILE
Marion Leydier

Marion Leydier

USA 2026

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Ranked in 1 practice area

About

Provided by Sullivan & Cromwell LLP

Practice Areas

General Practice

Artificial Intelligence

Capital Markets

Financial Services

Financial Services Mergers & Acquisitions

Insurance

Mergers & Acquisitions

Private Equity

Career

Marion Leydier is a partner in the Firm’s Insurance and Financial Services Groups. Ms. Leydier’s practice is primarily focused on domestic and cross-border M&A, private equity, restructuring and securities transactions involving insurance companies and other financial institutions, including banks, private equity funds and investment advisers, and the process of obtaining related regulatory approvals. Ms. Leydier also represents U.S. and international financial institutions in connection with a variety of matters before federal, state and international regulatory bodies. Ms. Leydier is a co-head of both the Firm’s global Insurance/Reinsurance Practice and North America Insurance Practice.

Professional Memberships

American Bar Association

New York City Bar Association

New York State Bar Association

Personal

Columbia Law School (J.D., 2001); Université de Paris I Panthéon-Sorbonne (D.E.A., 2001); Université de Paris I Panthéon-Sorbonne (Maitrise, 2000); ESSEC Business School (M.B.A., 1997)

Chambers Review

Provided by Chambers

Chambers Guide to the USA

Insurance: Transactional & Regulatory - New York

Band 3
Band 3

Individual Editorial
Marion Leydier advises clients on insurance M&A transactions, with additional expertise in regulatory matters. She is cohead of the firm's insurance practice.

Insurance: Transactional & Regulatory - USA - Nationwide

Band 3
Band 3

Individual Editorial

Marion Leydier represents large insurers in a wide array of transactional matters within the insurance industry, as well as advising on regulatory matters. She co-heads Sullivan & Cromwell's insurance practice.

Strengths

Provided by Chambers

  • Marion has the ability to seamlessly advise us on a practical level. She is really good at implementing things every step of the way from inception to closing.

    Insurance: Transactional & RegulatoryChambers Guide to the USA
  • Marion has very strong insurance regulatory expertise and a client-oriented approach.

    Insurance: Transactional & RegulatoryChambers Guide to the USA

Ranked Individuals at Sullivan & Cromwell LLP (144)

California

California: Los Angeles & Surrounds

California: San Francisco, Silicon Valley & Surrou

District of Columbia

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