Madelyn Petersen’s practice focuses on litigating class actions on behalf of consumers who have been misled, deceived or harmed by large corporations.
Prior to joining Cohen Milstein, Madelyn was a law fellow at the firm. In this role, she worked across practices and was involved in litigating individual and class action cases at the district and appellate levels. She was also a law clerk to the Honorable William Dimitrouleas of the United States District Court for the Southern District of Florida.
While at Harvard Law School, Madelyn was the managing editor of Harvard Journal of Law and Gender and online content editor for Harvard Civil Rights-Civil Liberties Law Review. While in law school, she was also a board member of the Harvard Prison Legal Assistance Project and participated in Harvard Law School’s International Human Rights Clinic. She was also a legal intern for the Corporate Accountability Lab, the Advancement Project, and Oxfam America.
- District of Columbia
- Harvard Law School, J.D., 2019
- University of Nebraska-Lincoln, B.A., 2016
Law Fellow, Cohen Milstein Sellers & Toll PLLC (2021 – 2022)
Law Clerk, Hon. William Dimitrouleas, U.S. District Court, Southern District of Florida (2019 -2021)
Current Cases
Baus, et al. v. Ford Motor Company
Baus, et al. v. Ford Motor Company (E.D. Mich.): Cohen Milstein represents plaintiffs who purchased or leased vehicles manufactured by Ford Motor Company in a consolidated breach of warranty and deceptive and fraudulent business practices class action against Ford Motor Company. Plaintiffs bring their claims under the Magnuson Moss Warranty Act and the consumer fraud statutes of their respective states, related to Ford’s manufacture and sale of defective Ford F-150 pickup trucks, Model Years 2018-2020 equipped with 5.0L engines.
Belyea, et al. v. GreenSky, Inc., et al.
Belyea, et al. v. GreenSky, Inc., et al. (N.D. Cal.): Cohen Milstein, as Co-Lead Counsel, is reparenting consumers in this putative false advertising and unfair business practices class action, alleging that GreenSky, a financial technology company, operates in California as an unlicensed and unregistered credit services organization, finance lender, and broker in violation of California Financing Law the Credit Services Act of 1984, and other federal and state laws.
DZ Reserve et al. v. Meta Platforms
DZ Reserve et al. v. Meta Platforms (N.D. Cal.): Cohen Milstein represents advertisers who claim that Facebook’s Potential Reach metric is false and misleading due to systemic inflation of the Potential Reach. The court granted class certification on March 29, 2022.
Siemens’ Arc Fault Circuit Interrupters (AFCI) Litigation
Plaintiffs claim that Siemens’ Arc Fault Circuit Interrupters (AFCI), a type of circuit breaker, are defective and Siemens misrepresents and omits information with respect to the quality of those AFCIs. Important Rulings Case Background Siemens is one of several companies that design and manufacture AFCI breakers. Plaintiffs claim that Siemens’ AFCIs fail to adequately distinguish […]
Past Cases
In re GreenSky Securities Litigation
In re GreenSky Securities Litigation (S.D.N.Y.): Cohen Milstein was Co-Lead Counsel in this securities class action involving fintech company GreenSky’s failure to disclose in its Initial Public Offering documents significant facts about the Company’s decision to pivot away from its most profitable line of business. This failure led to its stock plummeting and causing significant investor harm. In October 2021, the Court granted final approval of a $27.5 million settlement.
April 17, 2024
Second Class Action Filed Against General Motors for Defective Transmissions
Purchasers of new and used GM vehicles manufactured between 2015 – 2019 equipped with GM’s 8-speed transmission filed a product defect and consumer protection class action against GM for an alleged defective transmission design of GM’s Hydra-Matic 8L90 transmission or Hydra-Matic 8L45 transmission, which causes vehicles to suddenly lurch forward, shudder, and experience significant delays in acceleration. The plaintiffs in ten states claim GM was aware of the transmission defects that pose safety risks to drivers and passengers.
Press Releases | Cohen Milstein
March 22, 2024
9th Circ. Partially Backs Meta Class Cert. In Ad Reach Row
A split Ninth Circuit panel on Thursday affirmed certification of a damages class of Meta Platforms advertisers who were allegedly deceived about Facebook’s “potential reach” tool, but upended certification of an injunction class, telling the district court to take a fresh look at whether the lead plaintiff actually has standing. The panel majority, in a […]
In the News | Law360
March 22, 2024
Ninth Circuit Affirms Class Certification Against Meta Platforms
Consumer class action addresses Meta Platforms fraudulently misleading advertisers with inflated metrics about “potential reach.” WASHINGTON, DC– The United States Court of Appeals for the Ninth Circuit affirmed a district court’s 2022 order certifying a class of advertisers who paid Meta Platforms, Inc. (Meta) to place advertisements on its social media platforms (the damages class). […]
Press Releases | Cohen Milstein