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Matthew W. O’Neill


Matthew (Matt) O’Neill’s practice focuses on commercial litigation, arbitration, and appellate work. Matt has tried or arbitrated dozens of cases, representing both plaintiffs and defendants. Matters included shareholder disputes, contract disputes, employment litigation, securities arbitration, property disputes, and Chapter 11 bankruptcy. Matt has argued before the Wisconsin Supreme Court, Wisconsin Court of Appeals, and Seventh Circuit Court of Appeals.

Matt is well-versed in campaign finance and election law. In one election cycle, he helped obtain reversal of a criminal conviction against a former Republican lawmaker and represented the Democratic Party in a lawsuit protecting qualified voters from being removed from the poll books. Matt has successfully helped run several election recounts.

Matt helped litigate high-profile, “save the company” cases, including the reversal of a $100 million verdict against a local utility. Matt has obtained highly meaningful results for pro bono clients, including one that caused the world’s largest self-storage company to change its practices nationwide to ensure customers receive fair treatment.

Campaign Finance & Election Law



Civil Litigation

Represented minority shareholder in protracted derivative and direct litigation, including multiple trials and appeals.

Represented minority shareholder in federal trial regarding fair value of stock.

Argued two leading cases before Wisconsin Supreme Court involving minority shareholder rights.

Represented utility in appeal reversing $100 million punitive damages verdict.

Obtained $120,000 jury verdict for pro bono clients, including punitive damages, against major self-storage company.

Represented the spouse in divorce action against CEO of publicly traded corporation.

Obtained verdict clearing title and awarding damages in a property dispute between family members. Successfully defended verdict on appeal and thwarted attempted bankruptcy by obtaining ruling that the judgment was non-dischargeable.

Represented the ex-spouse in judicial dissolution case against former spouse to sever jointly owned business.

Obtained $900,000 arbitration award for wrongly terminated independent consultant.

Successfully litigated non-competition dispute on behalf of multinational industrial engineering company.

Obtained $2.1 million arbitration award for defrauded investor.

Successfully represented Board of Canvassers and defended recount of $1 billion school spending referendum.

Leader in the Law, 2020

Designated as Super Lawyer since 2006, recently named Wisconsin Top 50, Milwaukee Top 25

Received Legal Action of Wisconsin Exceptional Pro Bono Advocacy Award

State Bar of Wisconsin Pro Bono Honor Society

Past-President of Eastern District of Wisconsin Bar Association

Law Clerk, 1991-92, Wisconsin Supreme Court Chief Justice Nathan S. Heffernan (the best!)

Testified regarding election law before United States Congress, Wisconsin Senate and Wisconsin Government Accountability Board (now Wisconsin Ethics Board)

Selected, The Best Lawyers in America©

Board Member, ALS Association of Wisconsin

Board Member, Legal Action of Wisconsin

Board Member, Uptown Crossing Business Improvement District 16

Member, Serjeants Inn

Member, Thomas E. Fairchild Inns of Court

Fellow, Wisconsin Law Foundation

Member, Milwaukee Bar Association

Former Editor, Washington Heights quarterly newsletter, The Highlighter

Former Trustee and Secretary, Woodlands School Board of Trustees

Admitted, Wisconsin Supreme Court and all lower state courts

Admitted, United States District Courts for the Eastern and Western Districts

Admitted, Seventh Circuit Court of Appeals

Admitted, Ninth Circuit Court of Appeals

Admitted, United States Supreme Court

J.D., Marquette University Law School, 1991, magna cum laude

B.A., University of Notre Dame, 1988, cum laude

Matt was born and has lived in Milwaukee most of his life. He was paperboy for the Milwaukee Sentinel, rising early every day to deliver the news and Brewers box scores to a six-block stretch of loyal readers. He later painted houses and raised colonies of moths in a microbiology lab.

Matt is known for giving entertaining speeches (some in costume), running historic fantasy football leagues, and hosting epic vacations. The most epic were his 40th birthday party at a castle in Ireland, and his 50th birthday celebration at a palace in Italy (highlights available at

Matt is happily married with three interesting, diversely artistic daughters. In what spare time he has, Matt enjoys running, golfing, cooking, travel, solving and constructing crossword puzzles, and spending time with his dogs.