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John A. Coselli III

Senior Counsel

(713) 961-3366
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TransWestern Tower
1900 West Loop South
Suite 1000
Houston, TX 77027


J.D., South Texas College of Law, 2015

  • Phi Delta Phi International Legal Honor Society
  • Articles Editor, Texas Journal of Business Law
  • CALI Award Recipient

B.A., Government, University of Texas at Austin, 2011


John Coselli is Senior Counsel in the Houston office of GRSM. He represents and advises clients facing complex commercial litigation in state and federal courts throughout Texas.

John’s practice focuses on developing and implementing creative strategies both inside and outside of the courtroom to best achieve client interests. He handles a broad range of commercial matters including breaches of contract, partnership disputes, breaches of fiduciary duty, fraud, deceptive trade practices, and other issues affecting businesses and individuals.

Prior to joining GRSM, John spent years working as Associate General Counsel to a private corporation headquartered in Houston. In that position, he litigated a variety of disputes from beginning to end while gaining valuable perspective on the adversarial process through the lens of the litigant.


  • Texas
  • U.S. District Court, Southern, Western, Northern and Eastern Districts of Texas


  • State Bar of Texas
  • Houston Bar Association
  • Garland R. Walker American Inn of Court