Monica K. Loseman is a co-chair of Gibson, Dunn & Crutcher’s Securities Litigation Practice Group. Monica focuses her practice in corporate and securities litigation, investment advisor and fund litigation and investigations, financial reporting, accounting and related investigations, and accountant defense. She is a first chair trial lawyer, with trials in the Delaware Court of Chancery, bench and jury trials across the country, private arbitrations, and several trials before SEC administrative law judges.
Recognized by Chambers, Legal 500, Lawdragon, Benchmark Litigation, and Super Lawyers as a top-rated Securities Litigator, Monica has substantial experience in a variety of complex civil and corporate litigation matters. Chambers USA ranks Monica in its General Commercial Litigation and nationwide Accounting and Auditor Liability categories. The Legal 500 United States recognizes Monica as a “Leading Partner” in securities litigation defense and a recommended lawyer for M&A litigation defense. She was featured as one of Lawdragon’s “500 Leading Litigators in America” from 2023 to 2025, which recognizes “attorneys who excel representing principally corporations and other organizations in litigating claims.” She was also featured as a Law Week Colorado 2017 “Lawyer of the Year” and Denver Business Journal 2016 “40 under 40” Winner. Monica was also included in the 2024 edition of The Best Lawyers in America® for her work in Securities Regulation.
She defends companies and their officers and directors in class actions and derivative litigation and in regulatory investigations, including the Securities and Exchange Commission, Public Company Accounting Oversight Board, and the Department of Justice. Monica also has substantial experience in corporate governance matters, including litigation involving mergers and acquisitions and control disputes. She represents Board committees in conducting independent investigations involving allegations of corporate fraud and issues relating to financial reporting, accounting, internal controls, as well as special litigation matters and other issues, and is skilled at interacting with Board committees and other stakeholders in presenting results and recommendations. Clients have described Monica as an “excellent oral advocate, organized, to the point and very client-focused.”
Monica was appointed to the Financial Accounting Standards Advisory Council in 2023 and is currently serving her third term. She is a frequent speaker on securities litigation and SEC Enforcement matters and has co-authored several articles and contributed to texts regarding securities litigation topics.
Representative Matters
- Estée Lauder: Serving as lead counsel in a purported shareholder class action in the Southern District of New York involving alleged violations of Sections 10(b) and 20(a) of the Securities Exchange Act against the company, its former CEO and CFO.
- Alcon Inc.: Lead trial counsel in expedited litigation and trial in the Delaware Court of Chancery regarding preferred shareholder rights relating to ownership stake in early-stage med tech company and voting proxy; won voting rights claims and argued appeal in Delaware Supreme Court.
- Crocs, Inc.: Defending purported shareholder class action in the District of Delaware and various derivative litigation matters in federal and state courts in Colorado.
- Edward Jones: Won a significant summary judgment on all claims in purported nationwide investor class action in the Eastern District of California asserting so-called “reverse churning"; defending on appeal in the U.S. Court of Appeals for the Ninth Circuit.
- Hut 8 Corp.: Defending in a securities fraud class action pending in the Southern District of New York, as well as derivative litigation filed in Florida, New York, and Delaware. and various derivative litigation matters in federal and state courts in Florida and Delaware.
- Cassava Sciences, Inc.: Defending the company in the Western District of Texas against securities fraud claims related to alleged misrepresentations in connection with Phase 3 clinical trials and various derivative litigation matters in federal and state courts in Texas, Delaware and Illinois.
- Immunomedics, now owned by Gilead Sciences, Inc.: Defended purported shareholder class action in the District of New Jersey and various derivative litigation matters; settlement confirmed on favorable terms.
- Empower Retirement: Won dismissal in a putative multi-million member, nationwide investor class action in the District of Colorado. Gibson Dunn secured the win on a motion to dismiss.
- Leslie’s Inc.: Defending purported shareholder class action in the District of Arizona alleging misstatements in connection with the company’s revised earning guidance in 2023. Also defending derivative litigation matters in federal and state courts.
Monica has long been dedicated to pro bono work: in 2006, Monica was a member of the litigation team that received the Firm’s inaugural Frank Wheat Memorial Pro Bono Award for the team’s successful pro bono representation of a family seeking redress for multiple violations of their civil rights. She is a Past-President and previously served on the Executive Committee of the Board for Disability Law Colorado, an organization dedicated to the protection and promotion of people with disabilities in Colorado.
Monica attended the George Washington University Law School where she served as Editor-in-Chief of The George Washington Law Review and received several awards, including an award for completing her third year with the highest grade point average and the outstanding litigation student award. She graduated with high honors in 2002 and was elected to the Order of the Coif. She received her Bachelor of Science degree in management from Rensselaer Polytechnic Institute in 1997. Prior to attending law school, Monica was a consultant with KPMG Consulting in the Washington, DC area.
Monica is admitted to practice law in the States of Colorado, California and New York, the U.S. District Courts for the District of Colorado, and the U.S. Court of Appeals for the Sixth and Tenth Circuits.
Capabilities
- Securities Litigation
- Accounting Firm Advisory and Defense
- Anti-Corruption & FCPA
- Class Actions
- ESG: Risk, Litigation, and Reporting
- Law Firm Defense
- Litigation
- Securities Enforcement
- White Collar Defense and Investigations
Credentials
Education:
- George Washington University - 2002 Juris Doctor
- Rensselaer Polytechnic Institute - 1997 Bachelor of Science
Admissions:
- California Bar
- Colorado Bar
- New York Bar