Diane Sumoski
Partner
Business Litigation, Class Actions, Trade Secrets, Noncompetes, Probate and Trust & Estate Litigation
Phone: 214-855-3086
Direct Fax: 214-758-3786
Email: dsumoski@ccsb.com
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Ms. Sumoski has represented national and multinational corporations in a wide variety of complex business disputes, including matters of securities litigation, products liability litigation, breach of contract, and breach of fiduciary duty. Her practice has an emphasis on competition-related litigation, particularly relating to covenants not to compete, trade secrets, and breaches of confidentiality and fiduciary duty. Related to this focus, Ms. Sumoski also handles a wide variety of intellectual property litigation.
Ms. Sumoski also has considerable experience handling probate and trust and estate litigation matters, and working with individuals to resolve these cases either in or out of court.
Ms. Sumoski has extensive experience representing clients in class actions, including a number of such cases coordinated through the Judicial Panel on Multidistrict Litigation. She served on and coordinated the Ken Lay defense team in the Enron MDL proceeding. She also served as court appointed defense liaison counsel in a MDL class action venued in the Eastern District of Texas.
Ms. Sumoski represents clients in a wide range of industries, but she has particularly notable experience with clients in the technology, telecommunications, and food industries.
Ms. Sumoski has been listed in The Best Lawyers in America from 2010 to the present and in The Best Lawyers in America in Texas from 2010 to the present in the areas of commercial litigation and securities litigation. In addition, Ms. Sumoski has been designated by Texas Monthly magazine as a “Super Lawyer” in business litigation for 2011.
Ms. Sumoski enjoys serving the community and the bar through numerous activities, including as a member of the Board of Directors of the Dallas Bar Association, as pro bono counsel to the Board of Directors of the Dallas Contemporary, and as an active participant in the Dallas Volunteer Attorney Program. Ms. Sumoski serves as a member of the Firm’s four-person Executive Committee, and as the Co-chair of its Diversity Committee.
“I care about helping my clients resolve whatever their problems are. They are my focus, and my efforts are shaped by their specific needs. My goal is to figure out what’s right for them and get it done."
Representative Matters
Probate and Trust & Estate Litigation
Represented client in connection with a family dispute involving a family-held corporation owned by client, her siblings and her remaining living parent through a trust structure created in connection with the parents’ estate plan. Brought action on behalf of client and the family corporation to remedy undue influence of certain siblings in obtaining a larger than intended share of the family estate.
Trade Secrets/Non-Compete
Represented a telecommunications company in a series of matters that began when a competitor sought to enjoin four engineers, including a recently hired Vice President and Plant Manager, from joining client firm to develop a new product. Successfully defeated the TRO and Temporary Injunction, resulting in competitor voluntarily dismissing the suit. Continued representing the company in connection with trade secret challenges brought by yet another competitor regarding the new product and in an international arbitration with the Taiwanese subcontractor who developed certain aspects of the product.
Intellectual Property
Represented accused infringer of patented web site technology. Case was venued in the Eastern District of Texas.
Represented a standardized testing service in bringing claims for trademark infringement and copyright infringement, alleging that a test preparation company obtained unreleased copies of standardized tests to use with its clients.
Represented client in connection with claim against an employee pursuant to the Internet Corporation for Assigned Names and Numbers' Uniform Domain Name Dispute Resolution Policy and the Computer Piracy Act for misuse of client's domain name.
Class Actions and Multidistrict Litigation
Represented a Defendant Class in a ground-breaking class action in which a company and its insurers attempted to achieve a global settlement of their past and future asbestos liabilities.
Represented Ken Lay in the Enron MDL proceeding.
Represented a major food company in an MDL class action brought by consumers who claimed that genetically engineered corn infiltrated certain food products.
Represented outside directors in a securities class action brought as an MDL proceeding in which she acted as court-designated liaison counsel for all Defendants.
Pro Bono
Assisted a grandmother in adopting her grandson to enable him to enroll in school, obtain medical care, and ensure his clear right of inheritance of his grandmother’s worldly goods, including her modest home.
Education
Cornell Law School
J.D., cum laude, 1987
Associate, Cornell Law Review, 1985-
1986; Editor, 1986-1987
Recipient, John J. Kelly, Jr. Memorial
Prize, 1987
Franklin and Marshall College
B.A., 1984
Admittances
Texas 1987
Texas Supreme Court
U.S. District Courts for the Northern, Southern, Eastern, and Western Districts of Texas
U.S. Court of Appeals for the Fifth Circuit
Associations/Affiliations
Special Committee on the Future of Multidistrict Litigation of the American Bar Association, Section of Litigation, Co-Chair, 2009-2010.
Board of Directors of the Dallas Bar Association, 2009-present.
Dallas Bar Association, Continuing Legal Education Committee, Co-Chair, 2011.
Dallas Bar Association, Judicial Investiture Committee, Vice-Chair, 2011.
Director of Division VII, ABA Section of Litigation Public Service Division, 2008-2009.
Dallas Bar Association / Legal Aid of Northwest Texas, Equal Access to Justice Campaign, Chair, 2008-2009.
Dallas Bar Association / Legal Aid of Northwest Texas, Equal Access to Justice Campaign, Co-Chair, 2007-2008.
Dallas Bar Association Community Service Fund, Director 2008-present.
Dallas Bar Association Minority Participation Committee, Co-Chair, 2009.
Expert Witnesses Committee of the American Bar Association Section of Litigation, Chair, 2004-2008.
Dallas Bar Association Pro Bono Activities Committee, 1987-present. Co-Chair, 2008.
Dallas Bar Association, Summer Law Intern Committee, 2002-present; Vice-Chair, 2004-2006; Co-Chair, 2007.
Chair of the Host Committee for the 2002 Fifth Circuit Judicial Conference.
Director of Division IV of the American Bar Association Section of Litigation, 2000-2001.
Woman Advocate Committee of the American Bar Association Section of Litigation, Chair, 1998-2000.
American Bar Association Section of Litigation programming for the American Bar Association Annual Meeting, Chair, 1995-1996.
Fellow: American Bar Foundation
Life Fellow: Dallas Bar Foundation and Texas Bar Foundation
Member: American Intellectual Property Law Association, American Bar Association Section of Litigation and Intellectual Property Law Section, State Bar of Texas, Dallas Bar Association.
Speeches/Publications
Author, A Lawyer’s Professional Responsibility to Provide Pro Bono Legal Services, Dallas Bar Association Pro Bono Activities Committee Pro Bono Summit, 2008.
Author, Expert Advice: Practical Tips for the First Meeting With Your Expert, American Bar Association Annual Meeting, 2008.
Presenter, What Attorneys Want (And Sometimes Even Need) From Their Experts, Forensic Expert Witness Association Continuing Legal Education, May, 2008.
Presenter, Bridging the Gender Gap in the Courtroom, at the Connecticut Defense Lawyers Association’s 2007 “Women in the Courtroom” Continuing Legal Education.
Author, Bridging the Gender Gap, The Litigation Manual, First Supplement 2007.
Author, Enron: Navigating the Civil Side of the Corporate Case of the Century, American Bar Association Section of Litigation Annual Conference, San Antonio, 2007.
Presenter, Creating A Visual Strategy With Your Expert: Using Demonstratives With Expert Witnesses, American Bar Association Annual Meeting, San Francisco, 2007.
Moderator, Examining Expert Witnesses, American Bar Association Section of Litigation Annual Conference, Los Angeles, 2006.
Presenter, Discovery Problems and Their Solutions, American Bar Association Annual Meeting, Chicago 2005.
Litigation Against Bank Trust Departments; Will Contests and Other Probate Litigation; Fraud and Related Claims; The Hearsay Rule and its Exceptions - Articles included in materials presented at Continuing Legal Education courses.
Honors and Awards
Women’s Legal Advocacy Award from Legal Aid of Northwest Texas, 2010.
Named for inclusion in the 2010 and 2011 editions of the Best Lawyers in America.
Named for inclusion in the 2010 Dallas edition of Texas’ Best Lawyers in the area of commercial litigation.
Dallas Bar Association 2008 Joanna Moreland Outstanding Committee Chair Award.
Listed in the 2007-2008 30th Anniversary Edition of Who’s Who in American Law.
Dallas Volunteer Attorney Program Awards for Outstanding Pro Bono Coordinator, 1998, and Pro Bono Coordinator of the Year, 2005.
