Photo of Tor Gronborg

Tor Gronborg

Partner, Robbins Geller

619-231-1058torg@rgrdlaw.com

655 West Broadway
Suite 1900
San Diego, CA 92101

View Firm Biography

Tor Gronborg is a partner in Robbins Geller Rudman & Dowd LLP’s San Diego office and a member of the Firm’s Management Committee. He often lectures on topics such as the Federal Rules of Civil Procedure and electronic discovery. Gronborg has served as lead or co-lead counsel in numerous securities fraud cases that have collectively recovered more than $4.4 billion for investors. Most recently, Gronborg and a team of Robbins Geller attorneys obtained an $809 million settlement in In re Twitter, Inc. Sec. Litig., a case that did not settle until the day before trial was set to commence.

In addition to Twitter, Gronborg’s work has included significant recoveries against corporations such as Valeant Pharmaceuticals ($1.21 billion), Cardinal Health ($600 million), Motorola ($200 million), Duke Energy ($146.25 million), Sprint Nextel Corp. ($131 million), and Prison Realty ($104 million), to name a few. Gronborg was also a member of the Firm’s trial team in Hsu v. Puma Biotechnology, Inc., No. SACV15-0865 (C.D. Cal.), a securities fraud class action that resulted in a verdict in favor of investors after a two-week jury trial and ultimately settled for 100% of the claimed damages plus prejudgment interest.

Lawdragon Honors

Honor Year Practice
The 2026 Lawdragon 500 Leading Lawyers in America 2026 Plaintiff Securities Litigation
The 2025 Lawdragon 500 Leading Plaintiff Financial Lawyers 2025 Securities Litigation
The 2025 Lawdragon 500 Leading Lawyers in America 2025 Plaintiff Securities Litigation
The 2024 Lawdragon 500 Leading Plaintiff Financial Lawyers 2024 Securities Litigation
The 2024 Lawdragon 500 Leading Lawyers in America 2024 Plaintiff Securities Litigation
The 2023 Lawdragon 500 Leading Plaintiff Financial Lawyers 2023 Securities Litigation
The 2023 Lawdragon 500 Leading Lawyers in America 2023 Plaintiff Securities Litigation
The 2022 Lawdragon 500 Leading Plaintiff Financial Lawyers 2022 Securities Litigation
The 2022 Lawdragon 500 Leading Lawyers in America 2022 Plaintiff Securities Litigation
The 2021 Lawdragon 500 Leading Plaintiff Financial Lawyers 2021 Securities Litigation
The 2020 Lawdragon 500 Leading Plaintiff Financial Lawyers 2020 Securities Litigation
Lawdragon 500 Leading Plaintiff Financial Lawyers 2019 Securities Litigation

On three separate occasions, Gronborg’s pleadings have been upheld by the federal Courts of Appeals (Broudo v. Dura Pharms., Inc., 339 F.3d 933 (9th Cir. 2003), rev’d on other grounds, 544 U.S. 336 (2005); In re Daou Sys., 411 F.3d 1006 (9th Cir. 2005); Staehr v. Hartford Fin. Servs. Grp., 547 F.3d 406 (2d Cir. 2008)).

He earned his Bachelor of Arts degree from the University of California, Santa Barbara, and his Juris Doctor degree from the University of California, Berkeley, where he was a member of the Moot Court Board.