Tor  Gronborg

Tor Gronborg


There is no substitute for diligence.


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. Tor 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, Tor 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, Tor’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. Tor 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.

On three separate occasions, Tor’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)).

Tor has been named a Recommended Lawyer by The Legal 500, a Plaintiffs’ Lawyer Trailblazer by The National Law Journal, a Super Lawyer by Super Lawyers Magazine, and a Litigation Star by Benchmark Litigation. He has also been named a Leading Lawyer in America and a Leading Plaintiff Financial Lawyer by Lawdragon, a Best Lawyer in America by Best Lawyers®, and a West Trailblazer by The American Lawyer.

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.


  • Litigation Star, Benchmark Litigation, 2023-2024
  • Leading Plaintiff Financial Lawyer, Lawdragon, 2019-2024
  • Leading Lawyer in America, Lawdragon, 2022-2024
  • Best Lawyer in America, Best Lawyers®, 2022-2024
  • Recommended Lawyer, The Legal 500, 2023
  • West Trailblazer, The American Lawyer, 2022
  • Super Lawyer, Super Lawyers Magazine, 2013-2022
  • Plaintiffs’ Lawyer Trailblazer, The National Law Journal, 2019

Practice Areas


University of California at Berkeley, Boalt Hall, J.D., 1995

  • Member, Moot Court Board

University of Lancaster, United Kingdom, 1992

  • Graduate work in International Relations and Strategic Studies 
  • Rotary International Fellowship

University of California at Santa Barbara, B.A., 1991

  • Recipient, AFL-CIO History Scholarship


  • California
  • United States Courts of Appeals for the Third, Seventh and Ninth Circuits
  • United States District Courts for the Northern, Central and Southern Districts of California
  • United States District Court for the District of Colorado

Notable Cases


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