Kathryn L. Alessi

KATHRYN ALESSI, a partner in Sidley’s Boston office, focuses her practice on securities and shareholder litigation, governmental and regulatory investigations and enforcement proceedings, and complex business litigation. She holds various leadership positions within the firm, serving as co-chair of SidleyWomen for the Boston office and chair of the Committee for Evaluation and Compensation of Associates for the Boston office. Kathryn was selected as a “Top Women of Law” honoree by Massachusetts Lawyers Weekly in 2022.

For two decades, companies and individuals in the financial services, life sciences, healthcare, private equity and technology industries have relied upon Kathryn to navigate complex, high-stakes litigation matters, investigations, and enforcement proceedings involving allegations of misleading disclosures, securities fraud, accounting matters, sales practices violations, and breach of fiduciary duty, among other issues. Kathryn handles securities class action lawsuits, shareholder derivative litigation, mergers and acquisitions and other complex business litigation in state and federal courts nationally and locally in Massachusetts, as well as employment disputes in arbitral forums, often achieving dismissal of claims for clients. She frequently achieves favorable outcomes for clients in complex investigations and enforcement matters before the SEC, FINRA, state securities regulators, and the U.S. Department of Justice. Clients also turn to Kathryn to conduct internal investigations in response to allegations of wrongdoing. Beyond these active litigation, investigation, and enforcement matters, Kathryn counsels clients across a range of compliance and other matters, combining her legal knowledge with a practical approach to help clients minimize litigation and regulatory risk and achieve their business objectives.

In addition to Kathryn’s leadership roles at Sidley, she is actively engaged in civic service. In past years, Kathryn has served as Vice Chair of the planning committee for City Year’s Legal Community Breakfast in Boston, a program that has raised funds for Boston public school students with the aim of building a pipeline of future city leaders. She has also participated in the firm’s Veterans Advocacy Project, providing pro bono legal counsel assisting veterans with claims for service-connected disability compensation from the Department of Veterans Affairs.

Kathryn is a graduate of the University of California, Berkeley School of Law, where she was elected to the Order of the Coif, and received her undergraduate degree from Lafayette College, where she graduated first in her class. Prior to joining Sidley, Kathryn was a partner in the securities litigation and white collar defense group at a leading national law firm and, before that, clerked for The Honorable Franklin S. Van Antwerpen of the United States District Court for the Eastern District of Pennsylvania.

Representative Investigations and Enforcement Matters

• Achieved favorable outcomes for corporate and individual clients in investigations and enforcement matters before the SEC, FINRA, state securities regulators, and the U.S. Department of Justice in matters in the financial services, life sciences and healthcare industries involving a range of regulatory and legal issues, including, among others, disclosure matters, sales practices matters, the False Claims Act, and the Anti-Kickback Statute.
  • Represented a Fortune 100 company in an SEC investigation that the SEC closed without action. 
  • Represented one of the nation’s largest independent broker-dealers in resolving a multi-state investigation.
• Handled various internal corporate investigations for audit committees and other special board committees into financial accounting and corporate governance-related matters.*
• Served as one of several lawyers in private practice acting on behalf of the Massachusetts Attorney General’s Office in connection with civil and criminal matters relating to the Big Dig following the July 2006 Central Artery Tunnel collapse in Boston, which resulted in civil settlements of nearly $500 million on behalf of the Commonwealth.*

Representative Litigation Matters

• Obtained dismissal of a Massachusetts False Claims Act suit, and the subsequent affirmance by the Massachusetts Supreme Judicial Court, on the grounds that the suit was barred by the MFCA’s public disclosure bar.
• On behalf of Fidelity Brokerage Services and National Financial Services, obtained dismissal of putative class action filed in the Circuit Court of Jackson County, Missouri and removed to the U.S. District Court for the Western District of Missouri.
• On behalf of global oncology company and directors and executives, won dismissal on personal jurisdiction grounds of federal securities class action litigation concerning alleged misstatements in offering documents.
• On behalf of officers and directors of publicly traded company, secured complete dismissal of lawsuit asserting claims of violation of Section 10(b) of the Securities Exchange Act of 1934. Isham v. Perini Corp., 665 F. Supp. 2d 28 (D. Mass. 2009).*
• Represented public company boards of directors and acquiring corporations in shareholder litigation challenging mergers and acquisitions.
  • Obtained the dismissal before trial of shareholder class actions challenging various mergers, including the mergers of Epirus Biopharmaceuticals, Inc. and Zalicus Inc.*; AstraZeneca, Inc. and Omthera Pharmaceuticals, Inc.*; Royalty Pharma and Ramius LLC and Cypress Bioscience, Inc.*; Oracle Corporation and Phase Forward Incorporated*; Haemonetics, Inc. and Global Med Technologies, Inc.*; Syneron Medical Ltd. and Candela Corp.*; Dainippon Sumitomo Pharma Co., Ltd. and Sepracor, Inc.*; and Eastern Bank Corporation and MassBank Corp*.
• Represented private equity firms and their portfolio companies in transactional litigation and disputes.
  • Obtained Delaware Chancery Court ruling, in a matter of first impression, that, under Delaware General Corporation Law § 259, the seller’s attorney-client privileged communications, including the seller’s privileged communications concerning the merger transaction, vest in the surviving corporation following the merger, unless the parties contractually agree otherwise. Great Hill Equity Partners IV, LP v. SIG Growth Equity Fund I, LLLP, C.A. No. 7906CS (Del. Ch. Nov. 15, 2013).*

Employment Disputes

• Successful defense of a financial services firm in several FINRA employment arbitrations, in each obtaining a dismissal of all claims after hearing.
• Successful defense of a financial services firm in a JAMS employment arbitration, obtaining a dismissal of all claims after hearing.

*The matters denoted with an asterisk were handled by Kathryn prior to joining Sidley. 

• As Sidley’s Boston co-chair of SidleyWomen and Boston chair of the Committee for Evaluation and Compensation of Associates, Kathryn focuses on the firm’s recruitment and retention efforts and developing strategies to support and advance lawyers throughout their careers.
• Kathryn is a member of the American and Boston Bar Associations and has held prominent leadership positions in a variety of community organizations including:
  • Chair, Bowdoin College Parents Executive Committee (Present)
  • Global Advisory Board Member, Women in Law Empowerment Forum (2018–2024)
  • Member, Advisory Committee of the Boston Bar Association’s Women Leadership & Advancement Forum (2021–2022)
  • Vice Chair, City Year Boston Legal Community Breakfast Committee (2018–2020)
  • Co-Chair of Financial Services Section, Boston Bar Association (2017–2019)
  • Co-Chair of Civil Enforcement Committee, Boston Bar Association (2015–2017)