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Mark S. Deiermann

Mark S. Deiermann
  1. People /

Mark S. Deiermann

Mark S. Deiermann

Senior Counsel


St. Louis
Mark S. Deiermann
  1. People /

Mark S. Deiermann

Mark S. Deiermann

Senior Counsel


St. Louis

Mark S. Deiermann

Senior Counsel

St. Louis

T: +1 314 259 2449

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  • Biography

Biography

Mark is a litigator whose practice primarily involves commercial and business disputes. He has extensive experience in unfair competition matters, particularly in connection with covenant not to compete, trade secret and employee unfair competition disputes.

Mark has prepared a 50-state survey of the laws regarding noncompetition agreements in the United States, and also assisted in the preparation of a similar compilation covering the United States and several European countries for the TechLaw Group. He has been involved in more than 60 cases involving noncompete/trade secrets disputes; many more noncompete/trade secrets disputes which were resolved without the need for litigation; counseling many "old" employers, former employees and/or "new" employers regarding the enforceability of noncompetition provisions; drafting noncompetition agreements, reviewing the enforceability of noncompetition provisions contained in sale of business agreements; and providing advice and guidance to other attorneys within the firm in connection with noncompete disputes they are handling, including matters being handled in the firm’s other offices.

Civic Involvement & Honors

  • The Best Lawyers in America© Commercial Litigation, 2024
  • BTI Client Service All-Star, 2023

Admissions

  • Missouri, 1981

Education

University of Utah, J.D., Order of the Coif, 1981

University of Missouri-Columbia, B.A., 1978

Related Capabilities

Business & Commercial Disputes Business & Commercial Disputes

Non-Compete, Trade Secret & Employee Unfair Competition Non-Compete, Trade Secret & Employee Unfair Competition

Investigations Investigations

Regulation, Compliance & Advisory Regulation, Compliance & Advisory

Litigation & Dispute Resolution Litigation & Dispute Resolution

Employment Class & Collective Actions Employment Class & Collective Actions

Cross-border Employment Issues Cross-border Employment Issues

Higher Education Higher Education

Employment & Labor Employment & Labor

  • Business & Commercial Disputes

  • Non-Compete, Trade Secret & Employee Unfair Competition

  • Investigations

  • Regulation, Compliance & Advisory

  • Litigation & Dispute Resolution

  • Employment Class & Collective Actions

  • Cross-border Employment Issues

  • Higher Education

  • Employment & Labor

Related Insights

Awards
Aug 21, 2025

Best Lawyers in the USA 2026

Awards
Aug 17, 2023

The Best Lawyers in America® 2024

News
Jun 15, 2023

BCLP’s Mark Deiermann named BTI Client Service All Star 2023

News
May 02, 2023

BCLP team secures order blocking Missouri Attorney General’s Transgender Health Care Emergency Rule

Related Insights

Awards
Aug 21, 2025
Best Lawyers in the USA 2026
Awards
Aug 17, 2023
The Best Lawyers in America® 2024
News
Jun 15, 2023
BCLP’s Mark Deiermann named BTI Client Service All Star 2023
News
May 02, 2023
BCLP team secures order blocking Missouri Attorney General’s Transgender Health Care Emergency Rule
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