About Steve

Steven Tonsfeldt represents public and private companies in domestic and cross-border M&A transactions, contested transactions, hostile takeovers and defense planning. He also advises private investors and their portfolio companies on investment and acquisition transactions, and financial advisors working with companies engaged in transactional matters.

I work with companies on high-stakes, game-changing deals.

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Experience

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Rankings and accolades

Chambers USA: Corporate/M&A – California: San Francisco, Silicon Valley & Surro (2003 – 2025)

Lawdragon: 500 Leading Dealmakers in America (2021 – 2023)

Who's Who Legal: Thought Leader – M&A and Governance (2021 – 2023)

IFLR1000: Highly Regarded – Private Equity, M&A (California) (2020 – 2023)

The Legal 500 Recognized Attorney (2016, 2017, 2018, 2019, 2021, 2023)

The Legal 500 M&A Powerlist (2024)

Best Lawyers in America: Mergers & Acquisitions (2006 – 2023)

Memberships and affiliations

  • Berkeley Center for Law and Business – Executive Advisory Board
  • Certified Public Accountant

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