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Colleen M. O’Neil Partner

Colleen is a litigator in the Business, Corporate and Commercial Litigation group.

Colleen has extensive representative experience in federal and state courts on behalf of clients resolving disputes concerning:

>  Commercial contract disputes
>  Shareholder and corporate disputes, including post-closing issues
>  Estate and probate matters
>  Real property disputes
>  Employment and trade secret claims
>  Municipal and public law issues

Colleen has counseled and represented businesses, financial institutions and high net worth individuals in a variety of corporate, commercial, fiduciary and employment disputes with a results-oriented, practical approach.  She has successfully prosecuted and defended a variety of business tort claims in both federal and state courts.  Colleen has represented municipalities and clients in the energy industry in various types of litigation, including contractual disputes, real estate disputes and employment matters. 

Colleen has significant trial experience and success in her more than 20 years of practice and has extensive appellate experience appearing before the United States Courts of Appeals for the First, Fifth and Sixth Circuits, the United States Supreme Court and the Eighth District Court of Appeals of Ohio.

Colleen is a member of the Ohio and Cleveland Metropolitan Bar Associations and an active member of the American Bar Association’s Litigation Section.  She is a member of the firm’s Executive and Diversity Committees and is heavily involved in the community.  Colleen is privileged to serve on the Board of Directors of Magnificat High School, the Advisory Board to Metro Catholic School, and is a founding member of Cleveland’s Irish American Law Society.  She participated in the 2016 Leadership Cleveland Class.

She joined Calfee in 1998.