Securities Litigation

Weil is trusted by corporations and financial institutions, and their boards, officers and directors, to litigate and try significant securities, derivative, M&A, and financial products litigation cases; oversee sensitive internal and governmental investigations; and counsel clients on the full spectrum of business and corporate governance matters.

Notable Representations, Key Contacts

We offer our clients the resources of a dedicated, 65-lawyer practice that includes among its ranks a number of former federal prosecutors.

  • We excel at representing corporations and their directors and executives in shareholder litigation involving claims brought under the Securities Exchange Act of 1934 and the Securities Act of 1933. We have an excellent track record of success at the motion to dismiss and class certification phases, and are one of just a few firms to have tried these claims to a jury verdict.
  • We have coordinated the litigation and regulatory fallout from the financial crisis for companies such as AIG, Washington Mutual, Lehman Brothers, and Bear Stearns. This work has involved litigating claims in courts and arbitration venues across the country, as well as conducting investigations and regulatory proceedings before many U.S. agencies, the U.S. Congress, and international governmental entities, among others. Through these and other representations, we have unique experience litigating claims relating to complex structured products, including CDOs and CDSs. 
  • We work hand in glove with lawyers from our Corporate practices on all aspects of our clients’ most significant transactional matters, and have an extensive track record of successfully litigating attendant M&A litigation in Delaware and other courts in state and federal jurisdictions throughout the United States.
  • We counsel clients on the fiduciary duties of officers and directors of public and privately owned companies; counsel with respect to internal investigations commenced by audit and other board committees; oversee compliance with SEC and other regulatory guidelines; and manage investigations and enforcement proceedings initiated by the SEC, DOJ, FINRA, state attorneys general, and many other regulatory agencies.
Our clients count on our Securities Litigation practice in a range of areas:

Securities Fraud Class Actions

We regularly represent corporations and their directors and executives, as well as underwriters, in major securities fraud class actions alleging violations of the securities laws.

Shareholder Derivative Litigation

We have handled shareholder derivative actions in state and federal courts around the country, including cases in which shareholder plaintiffs have alleged that pre-suit demand is excused, cases in which pre-suit demands have been made and refused, and cases in which a demand was made for books and records in an effort to obtain discovery. We also have represented special litigation committees formed in response to shareholder demands or after derivative actions have been filed when demands were excused.

M&A Litigation

A significant part of our practice arises in the context of M&A and other change-of-control transactions. We work closely with the transaction team to preempt, defeat or resolve litigations seeking to block the consummation of deals in courts around the United States, including the Delaware Court of Chancery. We also have extensive experience defending companies in the Delaware Court of Chancery in appraisal actions.

Internal and Government Investigations

Whether in response to a government inquiry or on their own initiative, corporations, boards of directors, audit committees, and special board committees often engage our attorneys to conduct sensitive internal investigations. Our deep criminal and regulatory experience, coupled with the Firm’s strengths in class action litigation and corporate governance, enables us to conduct these investigations quickly, efficiently, and thoroughly, with due regard for how the investigation will affect subsequent criminal, regulatory, or civil litigation. We counsel our clients on how best to manage the results of any investigation and how best to control the complex risks confronting them.

Financial Products Litigation

Working closely and collaboratively with our Structured Finance and Corporate Governance groups, our Securities Litigation attorneys can successfully litigate (and explain) how these complex products work.
  • Weil’s Structured Finance and Derivatives practice has more than 35 lawyers worldwide. We were one of the first firms to combine securitization and derivatives capabilities to provide integrated solutions to complex disputes.
  • We possess deep experience in (i) the establishment of both cash flow and market value CDO/CLO vehicles, (ii) the documentation of credit default swaps with respect to super-senior CDO tranches for buyers and sellers, and (iii) customized repackaging programs for all types of investment instruments and structured investment vehicles.

Selected Representations

Securities Fraud Class Actions


lululemon athletica



Walgreens Boots Alliance

Willis Towers Watson

Shareholder Derivative Litigation

American International Group

General Electric


Liquidity Services

lululemon athletica

Special Committee of the Board of Massey Energy

M&A Litigation

Archstone, Lehman Brothers, and Tishman Speyer

Brookfield Asset Management


Elizabeth Arden, Inc.

Kinder Morgan

Lender Processing Services


Internal and Government Investigations


American Realty Capital Properties


Major Foreign Financial Institution

Confidential Health Industry Company

Confidential FCPA Investigations

Financial Products Litigation


Bear Stearns

Lehman Brothers


Key Contacts

John A. Neuwirth

John A. Neuwirth


New York

Caroline Zalka

Caroline Zalka


New York

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Recent Announcement

Weil is currently recognized among the top 10 securities litigation practices in New York and nationwide by Chambers USA, with sources noting “the team has stellar depth, with pragmatic thinkers [and] responsive senior lawyers” and "one of the things that sets Weil apart is their responsiveness. They definitely deliver value."

Chambers USA 2023

Weil is home to a ‘first-class’ white-collar and securities enforcement group.”

Benchmark Litigation, 2023

Weil is currently recognized as a top-ranked Tier 1 firm nationwide for both Securities Litigation: Defense and M&A: Litigation: Defense in Legal 500 US, which noted that “Weil has a dedicated team specializing solely in securities litigation. As a result, this is the only thing their litigators focus on and, by definition, they are experts in this field and the team drives exceptional results for their clients.”

Legal 500 US 2023

In each of 2016, 2017, and 2021, Weil was honored as a national Securities Practice Group of the Year


Weil is recognized as a top-ranked Tier 1 firm for Securities

Benchmark Litigation, 2024

Marketplace commentators praise our “organized and thoughtful litigators” who are “smart, responsive and terrific in court,” describe the quality of our work as “top-notch and without peer,” and highlight our team’s “stellar depth, with pragmatic thinkers, responsive senior lawyers and excellent writers.”

Chambers USA 2020-2023

Clients praise the “unrivaled success and experience and the creative and sophisticated approach” of our “exceptional litigators” who are “responsive, practical and deftly strategic” and “among the best of the best,” and further note how our team “drives successful results for their clients” in “high-profile matters that shape the future of the market.”

Legal 500 US 2016-2023

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