James R. "Sonny" Chastain, Jr.

Partner

  • Baton Rouge – Downtown
"I work closely with clients as a collaborative partner in all aspects of their business. Whether clients seek guidance on navigating complex litigation, negotiating or litigating contractual issues, or addressing business growth challenges, I am committed to helping them achieve their unique goals. I help our clients in protecting their intellectual property, providing business advice and in addressing commercial disputes of any type."

Commercial litigator and trusted advisor, Sonny Chastain, guides businesses and individuals through all types of complex federal and state court litigation claims. He also advises on the ownership and protection, of critical intellectual property assets.

Sonny serves as counsel on all types of contract negotiation and commercial litigation, banking litigation and consumer finance, breach of fiduciary duty, and unfair trade practices. He advises on issues involving truth in lending, fair debt collection practices, antitrust law, RICO matters, employment/non-compete agreements, software licensing, arbitration agreements, investment suitability, and broker relations.

Moreover, Sonny navigates clients through copyright and trademark registration prosecution, brand management, and IP infringement litigation. He also addresses insurance coverage disputes and serves as a mediator in commercial disputes, injury/property damage, and insurance coverage claims.

Sonny’s clients benefit from his effective advocacy skills and practical business advice. He is valued for his candid, clear, and practical counseling style that keeps clients fully apprised of the law, their options, and the status of their matter.

Outside the courtroom, Sonny is well-versed in handling arbitrations and mediations involving intellectual property and other business disagreements. Beyond advocacy, Sonny regularly counsels clients on all types of commercial and IP-driven transactions, a sampling of which includes licensing, employment, franchise, and development agreements.

Sonny’s character, judgment, business and legal acumen, and multi-dimensional understanding of the underlying causes that drive a dispute are the result of decades of hard-earned experience. Sonny delivers a creative and balanced approach to problem-solving, collaborating with his clients to flourish.

  • LSU Law Center, J.D., 1989
  • LSU, B.S., Finance, 1986
    • Member, Sigma Chi Fraternity

Bar Admissions

  • Louisiana

Courts

  • U.S. District Court for the Eastern District of Louisiana
  • U.S. District Court for the Middle District of Louisiana
  • U.S. District Court for the Western District of Louisiana
  • U.S. Court of Appeals, Fifth Circuit
  • U.S. Supreme Court
  • AV Preeminent-rated, Martindale-Hubbell
  • “Best Lawyers,” The Best Lawyers in America, 2015-2026
  • “Lawyer of the Year,” The Best Lawyers in America, 2018, 2021, 2023, 2025
  • “Capital Region 500,” Baton Rouge Business Report, 2023-2026
  • “Super Lawyers,” Louisiana Super Lawyers, 2014-2015, 2022-2026
  • “Client Service All-Star,” BTI, 2022
  • “Forty Under 40,” Baton Rouge Business Report, 1999