Biography

John Thornton brings over a decade of diverse legal experience to his clients, including roles as a litigator in private practice and as the Chief Legal Officer at a mid-sized professional services company. Having directly reported to the chief executive officer and worked with the board of directors, John understands what internal stakeholders expect from outside counsel—not merely a lawyer, but a counselor to navigate their most challenging legal matters and to guide them to the most pragmatic business solutions.

Litigation

John has represented clients in trial and appellate litigation matters, including breach of contract, breach of fiduciary duty, fraud-related claims, conversion, defamation, employment and labor, conflicts of interest and legal ethics, tortious interference, and deceptive and unfair trade practices, among other matters.

Corporate Counsel

John’s in-house experience includes providing corporate governance and other advice, advising on employment and labor matters, drafting and negotiating complex transactions including master services agreements, subcontracts, teaming agreements, nondisclosure agreements, UCC Article 9 matters and other transactions.

Background

Prior to joining Armstrong Teasdale, John was the Chief Legal Officer for a Florida-based management consulting company with a national presence. Before that, he was an attorney at two multinational law firms and a Miami litigation boutique. In addition, he clerked for the Hon. Donald L. Graham in the U.S. District Court for the Southern District of Florida.

Education

  • University of California, Berkeley, Boalt Hall School of Law
    • Executive Education
  • University of Miami School of Law  (J.D., cum laude, 2014)
    • University of Miami Inter-American Law Review, Articles and Comments Editor
    • Dean’s Certificate of Achievement Award, Death Penalty Clinic
  • University of Florida, Warrington College of Business  (B.S.B.A., 2011)

Admissions

  • Florida
  • Illinois

Professional Activities

  • South Florida Chapter of the Federal Bar Association, Director

Charitable and Civic Involvement

  • Legal Services of Greater Miami, Inc., Director
  • Leadership Florida, Connect Class XIII & Southeast Regional Council

Languages

  • Spanish (proficient)

Highlights

News Item

Missouri Lawyers Weekly Names Ty Ketchum to 2026 Employment Law Power List

Tyson Ketchum
News Item

Partners Lam, Waldman Quoted in National Media on Biscayne 21 Settlement

Jeffrey Lam and Glen Waldman
News Item

Armstrong Teasdale Secures Possession of Two Chicago High-Rises in Ground Lease Litigation

An Armstrong Teasdale litigation team successfully secured possession for its clients of two high-rises located on the 800 West block of Jackson Boulevard in Chicago, delivering a significant victory for the ground lessors in...

Thought Leadership

Colorado A-Companies: Options for Artists and Investors Nationwide

Advisory
Experience

Formation of Equity Joint Venture for $1 Billion Insurance Consortium

Represented a non-controlling owner in the formation of an equity joint venture that served as a managing general underwriter for a consortium of insurance companies with more than $1 billion in annual revenues, and...

Event

Protect, Prevent, Defend: An In-House Counsel's IP Playbook

This CLE will provide in-house counsel with a practical framework for identifying, protecting, and defending their company’s intellectual property—from overlooked brand elements and creative works to innovations, software, and business processes. We’ll explore how...

Thought Leadership

Supreme Court Upholds SEC’s Disgorgement Power But Leaves Some Questions Unanswered

Advisory
Thought Leadership

What To Expect From Colorado's New Artist Co. Structure

Colorado recently enacted the Colorado Artist Company Act, a first-of-its-kind statute creating artist companies, or A-Corps — a variant of a Colorado limited liability company with certain artist-friendly default provisions. The act became effective...

Thought Leadership

Standards of Review Take Center Stage in Trademark Case Accepted by SCOTUS

Kyle Gottuso and Blake Chrismer
News Item

Armstrong Teasdale Named a Champion for Diversity & Inclusion

Armstrong Teasdale has been named a Champion for Diversity & Inclusion by the St. Louis Business Journal. The firm was recognized for its sponsorship and mentorship programs, leadership development, employee resource groups, and workplace...

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