Mark R. Clasby

Mark R. Clasby

Attorney, O'Neil Wysocki, P.C.

Mark Clasby approaches the practice of law with the critical thinking skills and preparation for a strategic battle. His fundamental tenants are 1) analyze everything and take nothing for granted because things are not always as they seem; 2 prepare thoroughly before rushing into anything; and 3) teamwork is essential to success of the mission, as every member of a client’s team is essential to success of a client’s mission, from the client to the lawyer, from the paralegal to the witnesses.

For over a decade prior to attending law school, Mark worked in the legal industry as a discovery consultant, managing document production projects and assisting firms in navigating the unchartered electronic discovery arena. Now, as a graduate of Texas A&M School of Law, Mark extends that expertise to his clients by assisting in requesting the relevant information pertinent to a case and seeking out the useful gems in the opposing side’s responses to discovery. As electronic discovery continues to progress, Mark’s technological skill lends to better organization and perspective in his cases.

As a trained communicator and mediator, Mark is also known to his clients and colleagues for his ability to provide creative solutions to their individual situations. Yet, his hard work and determination make him a credible foe in the courtroom. He believes that the best leverage to encourage settlement is preparation for the battle.

Mark lives in the Dallas area with his new wife Amanda and their dog Toby.

Bar Membership

  • State Bar of Texas, June 2014


  • J.D., Texas A&M School of Law, 2014
  • B.A. Communications, Austin College, 2004
  • Mediation Certificate, 2013

Professional Affiliations

  • Dallas Association of Young Lawyers – Social Committee
  • Dallas Association of Young Lawyers 2016 Leadership Class
  • DAYL Foundation Fellow
  • State Bar of Texas – Family and LGBT Sections
  • Dallas Bar Association
  • BNI Referral Experts

Speaking Engagements

  • Panelist, The Pressures of Law School & Practicing Law, UNT Law School, October 2016
  • Panelist, Restorative Justice Conference, Dispute Resolution Services of North Texas, May 2014


  • Tips for Young Lawyers, TYLA eNews, December 2014

5323 Spring Valley Road #150
Dallas, TX 75254

Learn How O’Neil Wysocki P.C. Can Help You We are ready to stand by your side from start to finish. Call (972) 852-8000 or email us below to schedule your consultation.
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