LAWYER PROFILE
William Dalsen

William Dalsen

USA 2026

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Ranked in 1 practice area

About

Provided by Proskauer Rose LLP

USA

Practice Areas

Will Dalsen is a senior counsel in Proskauer's Litigation Department. An experienced litigator and trial lawyer, Will focuses on complex commercial litigation and high-stakes trials with a particular emphasis on asset management, antitrust, healthcare and bankruptcy litigation.

Will has litigated a range of matters in federal courts, including serving as a key member of the trial team that secured a complete defense verdict on behalf of Gilead Sciences, Inc., Gilead Holdings, LLC and Gilead Sciences, LLC in a $3.6 billion antitrust case on allegations that the pharmaceutical company struck an anticompetitive "pay-for-delay" patent settlement related to two HIV medications. He has also served as lead trial counsel and led every phrase of the litigation process in numerous cases throughout the United States.

Will routinely represents funds, fund sponsors, portfolio companies and their officers and directors, including in significant post-closing M&A disputes. He is highly regarded for his deep knowledge of the private credit and private investment fund industries as well as his ability to provide counseling and resolve disputes for both sponsors and portfolio companies.

Prior to joining Proskauer, Will served for two years as a law clerk to Judge Susan Phillips Read of the New York State Court of Appeals, drafting bench memoranda and assisting with opinions in a variety of civil and criminal matters. While in law school, Will was Editor-in-Chief of the Wisconsin Law Review and served as a judicial intern to the Honorable Shirley S. Abrahamson, Chief Justice of the Wisconsin Supreme Court.

Chambers Review

Provided by Chambers

Chambers Guide to the USA

Litigation: General Commercial - Massachusetts

Up-and-coming Individual
Up and Coming

Individual Editorial

William Dalsen has a growing practice representing a range of asset management firms in commercial litigation.

Strengths

Provided by Chambers

  • William Dalsen is a really strong litigator who is dogged in his approach.

    Litigation: General CommercialChambers Guide to the USA
  • William is a highly talented commercial litigator.

    Litigation: General CommercialChambers Guide to the USA

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