William Sinclair - Best Lawyers
William Sinclair - Super Lawyers

Bill Sinclair is the partner in charge of the firm’s Business Litigation Group. His practice covers white-collar criminal defense and complex civil litigation. He also handles select personal injury and transactional matters. Notably, Mr. Sinclair leads his team to efficiently and effectively manage complex legal issues, and excels in anticipating client needs and potential challenges, whatever their case.  

Bill Sinclair’s clients have included corporations, individuals, and public agencies and utilities in toxic tort, environmental, and product liability cases; personal injury matters; civil rights cases; commercial, business and employment matters; land use, construction and other real estate disputes; and environmental, health care, and securities enforcement proceedings and investigations as well as other complex crimes.  

One of the best business litigation lawyers in Maryland, Mr. Sinclair helped found and grow the sophisticated business litigation and counseling practice at the Firm. His areas of expertise range from defense of professionals, to appeals and construction litigation. In recent years, Mr. Sinclair has tried jury and non-jury civil matters as both plaintiff’s and defense counsel, as well as criminal matters, in state and federal courts in the District of Columbia and Maryland. He has also argued before the United States Courts of Appeals for the Fourth and Ninth Circuits, the Appellate Court of Maryland, and state and federal trial courts in California, Delaware, the District of Columbia, Georgia, Maryland, Minnesota, New Jersey, and Virginia.  

Mr. Sinclair is consistently selected by his peers as a top lawyer in Maryland.   


Patti Oxenford

Office: 410.385.2225

Direct: 410.385.9116

Fax: 410.547.2432

  • University of Virginia School of Law - J.D. - 2002
  • University of California at San Diego - B.A. - 1999

    Magna Cum Laude

Practice Areas
  • Defense of Professionals
  • Appellate / Civil Appeals
  • Criminal Defense-White Collar
  • Real Estate
  • Business Litigation
  • Construction Litigation
  • Environmental Law
  • Investigations & White Collar Defense
  • Labor & Employment
  • State and Local Government
Significant Cases
Mr. Sinclair has served, or serves, as (co-) lead, or local, plaintiff’s and defense counsel in several class action and other complex litigation matters, including:
  • Local counsel for a Global Fortune 50 energy company in defense of putative class action climate change litigation in Maryland’s federal and state courts;
  • Co-lead counsel for the State of Maryland and Baltimore County in the opioids litigation;
  • Local counsel in a securities action for a class recently approved by the U.S. District Court, see In re: Under Armour Sec. Litig., -- F. Supp. 3d ---, 2022 WL 4545286 (D. Md. Sept. 29, 2022);
  • Local counsel in putative class action against local university for breach of contract claims relating to how it handled in-person student classes and living during the COVID pandemic;
  • Local counsel in putative class against Johns Hopkins University for wage and hour violations;
  • Lead counsel in defense of putative class action in California for wage and hour violations; and
  • Co-lead counsel in successful putative class action against the National Hockey League regarding concussions
Government Service
  • Law Clerk, Hon. C. Christopher Hagy, U.S. District Court for the Northern District of Georgia, 2003-2004
  • Best Lawyers, 2021-2024
  • Maryland Super Lawyers, 2014-2024
  • Maryland Top 100, 2017-2018

Who Rules the Roost? CWA Liability After Md. Ruling, Product Liability Law360, Portfolio Media Group (September 2010)

Status Check: Assessing Interior’s Implementation of the Energy Policy Act of 2005, Sustainable Development Law & Policy, Vol. VII, Issue 3 (Spring 2007)

Future of the “Feeney Amendment” After High Court’s Sentencing Rulings, Legal Backgrounder, 2005


Panelist for Maryland State Bar Association Annual Conference, September 23, 2020 (presenting to the State Bar a program entitled: The Next Wave: Transitioning Law Firm Management, along with managing partners from Saul Ewing, Miles & Stockbridge, and Offit Kurman)

Panelist at American University Washington College of Law, March 1, 2019 (presenting to the American University Sports and Entertainment Law Fall Symposium on issues relating to amateur status in sports)

Panelist at American University Washington College of Law, October 20, 2017 (presenting to the American University Sports and Entertainment Law Fall Symposium on concussion issues)

Panelist for Anne Arundel County Bar Association Annual Meeting, March 4, 2017 (presenting on issues of fiduciary litigation, business valuation and business "divorce")

Panelist at the University of Virginia School of Law, February 10, 2017 (presenting to the University of Virginia Sports Law Symposium on concussion issues)

Teaching Experience
University of Maryland School of Law, Adjunct Professor, 2009-Present
Professional & Bar Association Memberships
  • Maryland Bar Foundation
  • Maryland State Bar Association

    Former Chair, Membership Committee
    Member, Committee on Laws
    Former Fellow, Leadership Academy

  • Bar Association for Baltimore City
  • Baltimore County Bar Association
  • The District of Columbia Bar
  • State Bar of California
  • State Bar of Georgia
  • One Love, Maryland Regional Council


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