John A. Yanchunis, Class Action Attorney in Tampa, Florida

John A. Yanchunis leads the Class Action Department of the firm. Mr. Yanchunis’ practice- which began after completing a two-year clerkship with United States District Judge Carl O. Bue, Jr., Southern District of Texas-has concentrated on complex litigation and spans over 36 years, including class actions for almost two-thirds of that time.

Mr. Yanchunis has served as lead, co-lead, or class counsel in numerous class actions in a wide variety of areas affecting consumers, including but not limited to anti-trust, civil rights, defective products, environmental claims, life insurance, annuities, and unfair and deceptive practices. He has been appointed by courts to leadership positions in multidistrict class action litigation, and presently serves as the lead in In re: Yahoo! Inc. Customer Data Breach Security Litigation, 5:16-md-02752 (N.D. Cal.), as a member of the plaintiffs’ steering committee In re Equifax, Inc. Customer Data Sec. Breach Litig., 1:17-md-02800 (N.D. Ga.); on the three-member Plaintiffs’ Steering Committee in MDL No. 2664, In re: U.S. Office Personnel Management Data Security Breach Litigation, and serves on the Executive Committee overseeing the consumer class, the financial institution class, and the shareholder derivative litigation pending against Target Corporation-one of the largest data-breach cases to date-in In re Target Corporation Customer Data Security Breach Litigation, MDL No. 2522 (D. Minn.).

As a result of his experience in insurance and complex litigation, beginning in 2005, Mr. Yanchunis served as lead counsel for the Florida Department of Financial Services and the Florida Department of Insurance Regulation (the insurance regulators of Florida) in their investigation of the insurance industry on issues concerning possible antitrust activity and other possible unlawful activities regarding the payment of undisclosed compensation to insurance brokers. Mr. Yanchunis served as lead regulator counsel and worked with a core group of state Attorneys General from the National Association of Attorneys General, which were selected to conduct the investigations. The insurance regulators for Florida was the only insurance regulators in the group. The litigation that was filed and the other investigations recovered millions of dollars in restitution for Florida consumers and resulted in significant changes in the way commercial insurance is sold in Florida and across the country.

During his career, Mr. Yanchunis has tried numerous cases in state and federal courts, including one of the largest and longest insurance coverage cases in U.S. history, which was filed in 1991 by The Celotex Corporation and its subsidiary, Carey Canada, Inc. During the seventeen years the case was pending, Mr. Yanchunis served as lead counsel for several insurance companies, regarding coverage for asbestos and environmental claims. The case was tried in three phases over several years beginning in 1992. Mr. Yanchunis was also lead counsel for these parties in the subsequent appeals which followed a judgment in favor of his clients.

Mr. Yanchunis served as an elected member of the Young Lawyers Board of Governors (two terms) and Board of Governors of The Florida Bar (the governing body of The Florida Bar) (two terms), served as a member of The Board of Directors of The Florida Bar Foundation, and was appointed by The Supreme Court of Florida to serve as a member The Florida Board of Bar Examiners. After the completion of his five-year term on the Board of Bar Examiners, Mr. Yanchunis has been reappointed annually by the Florida Supreme Court since 2002 to serve as an Emeritus Member on character and fitness panels and as an arbiter in final hearings.

Mr. Yanchunis has also served on many committees of The Florida Bar, including leadership positions. Most recently, he completed a term as the Chair of the Consumer Protection Committee of the Florida Bar. Mr. Yanchunis has also represented The Florida Bar in a number of matters. He was also appointed by the Florida Supreme Court to enforce an injunction of the Court, and his efforts resulted in the incarceration of the respondent in that case on the finding that the respondent had engaged in indirect criminal contempt. As a result of his experience in the area of class litigation and ethics, he has served as an expert for The Florida Bar on ethical issues arising in class action litigation.

He received the Elder Law Section of The Florida Bar awarded him its Chair’s Honor Award for Mr. Yanchunis’ handling with one of his law partners of a class action against the state of Florida for violations of federal law in failing to deliver a benefit under Medicaid to approximately 41,000 elderly residents of nursing homes in Florida. He is also the recipient of The Florida Bar Foundation President’s Award for Excellence for his outstanding leadership in promoting the Foundation’s mission to help provide legal assistance for the poor.

Mr. Yanchunis frequently lectures around the United States on topics related to class actions.

In the community, Mr. Yanchunis served as a member of the Elder Law Board, College of Law and the Center for Excellence in Elder Law, Stetson University College of Law. He has been a member of the Boy Scouts of America since his youth having earned the rank of Eagle, and has served in virtually every leadership position as an adult leader in Cub Scouts and Boy Scouts, including as Council President to the West Central Florida Council of the Boy Scouts of America, and as a member of National Council of the Boy Scouts of America.

Mr. Yanchunis is a member of The Florida Bar (admitted in 1981). Additionally, he is admitted to the United States Supreme Court; the United States Courts of Appeal for the Fifth, Sixth, Seventh, Ninth, and Eleventh Circuits; the United States District Court for the Southern, Northern, and Western Districts of Texas; the United States District Court for the Eastern and Western Districts of Wisconsin; the United States District Court for the Middle and Southern Districts of Florida; the United States District Court for the Eastern District of Michigan; the United States District Court for the Western District of Kentucky; the United States District Court for the Northern District of Illinois; the United States District Court of Connecticut; and the United States District Court of Colorado.

Martindale-Hubbell has honored Mr. Yanchunis with the prestigious “AV” rating. He has been recognized continuously as a Florida Super Lawyer and The Best Lawyers in America in his area of practice. He is a fellow in The Trial Lawyer Honorary Society of the Litigation Counsel of America, and a fellow of The Florida Bar Foundation.

While at the University of Florida Mr. Yanchunis was a member of Florida Blue Key and Omicron Delta Kappa. He received his Juris Doctor degree from the South Texas College of Law in 1980, where he graduated magna cum laude. During law school, Mr. Yanchunis was a member of the Order of the Lytae, Associate Editor-in-Chief and Technical Editor of the South Texas Law Journal.

Awards & Recognitions

•Lawdragon 500 Global Plaintiff Lawyers, 2026

Recent Wins

Rodriguez v. Google $425,651,947 Data Privacy 2025

Equifax, Inc., Customer Data Security Breach Litigation $380,500,000 Data Privacy 2020

Merrimack Valley Gas Explosion $143,000,000 Catastrophic Event, Explosions 2021

Yahoo! Inc. Customer Data Security Breach Litigation $117,500,000 Data Privacy 2020

U.S. OPM Data Security Breach Litigation $63,000,000 Data Privacy 2022

MGM Resorts Data Breach $45,000,000 Data Privacy, Class Action 2025

Richards et al. v. Chime Financial, Inc., et al. $12,462,563 Class Action 2019

Roberts et al. v. AT&T Mobility LLC $12,000,000 Data Privacy 2021

Google Plus Profile Litigation $7,500,000 Data Privacy 2021

Guidry v. Penn Credit $4,675,000 Data Privacy 2020

Kukorinis v. Walmart Stores, Inc. $4,500,000 2021

Kalispell Regional HealthCare Data Breach $4,200,000 Data Privacy 2021

Pfeiffer v. RadNet, Inc. $2,600,000 Data Privacy 2020

Citrix Data Breach Litigation $2,275,000 Data Privacy 2020

Heather Huddleston v. Florida Hospital $2,090,000 Whistleblower & Qui Tam 2016

Kelly Oxendine v. HCA $2,000,000 Whistleblower & Qui Tam 2017

Siwicki, Kathleen v. Portnow, Arthur S., M.D. $1,950,000 Whistleblower & Qui Tam 2017

Doe v. Centerstone of Tennessee, Inc., et al. $1,500,000 Data Privacy 2021

Llamas v. TrueFire LLC $1,200,000 Data Privacy 2021