Claire Marsden is an associate in Cohen Milstein’s Securities Litigation & Investor Protection practice, where she represents investors in shareholder derivative lawsuits and securities class actions.
Prior to joining Cohen Milstein, Claire was a law clerk for the Honorable Ann M. Donnelly of the United States District Court for the Eastern District of New York.
Before her judicial clerkship, Claire was an associate at a highly regarded global defense firm, where she focused on securities, antitrust, RICO, Foreign Sovereign Immunities Act, and other white collar-related issues. She was also involved in a variety of pro bono matters related to prisoner’s rights and fair sentencing, and she spent six months as a full-time secondee with the Office of the Federal Public Defender for the Eastern District of Virginia.
While attending Columbia Law School, Claire was a Harlan Fiske Stone Scholar and executive articles editor of A Jailhouse Lawyer’s Manual, a handbook of legal rights and procedures designed for use by currently incarcerated people. She also served as a law clerk at the U.S. Senate Judiciary Committee.
- District of Columbia
- New York
- Columbia Law School, J.D., 2019
- Occidental College, B.A., magna cum laude, 2014
Law Clerk, the Hon. Ann M. Donnelly, U.S. District Court, Eastern District of New York (2023 – 2024)
Current Cases
Illumina Stockholder Derivative Litigation
The Pavers and Road Builders Benefit Funds v. deSouza, et al. (Del. Ch.): Cohen Milstein represents stockholders in a derivative lawsuit against the board of directors of Illumina, Inc., a biotech company, for flagrant breaches of fiduciary duty and positive law related to Illumina’s $8 billion reacquisition of GRAIL, a healthcare company. Stockholders claim that the board’s decision to close the merger violated binding standstill obligations under Article 7(1) of the European Union Merger Regulation and flouted U.S. antitrust law, exposing Illumina to regulatory scrutiny and massive fines.