LAWYER PROFILE
Rachel Mossman Zieminski

Rachel Mossman Zieminski

USA 2026

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Ranked in 1 practice area

About

Provided by A&O Shearman

USA

Practice Areas

Rachel is an experienced litigator and trial attorney representing clients in some of the most complex and significant antitrust disputes in the market today. These include cases challenging clients’ intellectual property under antitrust theories, defending clients’ hiring practices against “no-poach” challenges, and defending mergers in trials against the Department of Justice.

Rachel has over a decade of experience in antitrust cases involving healthcare and represents clients across industries including health insurance, retail, payment processing, aviation, book publishing, defense contracting, and private equity.

Rachel has a passion for fact gathering and a unique ability to distill complicated antitrust arguments into easy-to-understand narratives. These skills allow Rachel to develop strong discovery records and compelling arguments in support of her clients’ positions.

Chambers Review

Provided by Chambers

Chambers Guide to the USA

Antitrust - Texas

Up-and-coming Individual
Up and Coming

Individual Editorial

Rachel Mossman Zieminski of A&O Shearman is an up-and-coming attorney who advises clients on complex antitrust litigation. She regularly handles price-fixing and monopolization cases.

Strengths

Provided by Chambers

  • Rachel is an excellent lawyer who is bright and very promising.

    AntitrustChambers Guide to the USA
  • Rachel is a rising star.

    AntitrustChambers Guide to the USA

Ranked Individuals at A&O Shearman (79)

California

California: San Francisco, Silicon Valley & Surrou

District of Columbia

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New York

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