Marian P. Rosner
Of Counsel

Marian P. Rosner

Practice Areas


  • Brooklyn Law School (J.D., 1973)
  • New York University (B.A., 1970)

Bar Admission

  • New York State
  • United States Supreme Court
  • U.S. Court of Appeals for the Second, Third, Eight and Ninth Circuits

Ms. Rosner has been successfully litigating securities and ERISA class actions for decades on behalf of injured investors.

Marian P. Rosner is Of Counsel to Wolf Popper LLP, ("Wolf Popper" or "the Firm").  Ms. Rosner is a graduate of New York University (B.A., 1970) and from Brooklyn Law School (J.D., 1973). She served as an Assistant Corporation Counsel for the City of New York Law Department, General Litigation Division, before joining Wolf Popper in 1976.  She became a partner in 1981.

Ms. Rosner has litigated securities class actions for over forty-five years and is widely recognized as one of the few women lawyers at the top of her field.  In 1982, when Ms Rosner was only 32 , the late Mary Johnson Lowe appointed Ms Rosner as sole lead counsel in the consolidated action In Re  Saxon.Sec Litig., 82 Civ. 3101(S.D.N.Y), stating that she was proud to see a woman lawyer serving as lead counsel in a major securities case. The case settled in 1985, 3 years later for a global settlement of $80 million with the securities class action achieving equal status in the settlement with the bondholders who brought a companion action and had a higher status in bankruptcy than did the shareholders. The next year, In 1986, Ms Rosner went onto serve as sole Chair of Plaintiffs Executive and Scheduling Committees  in the national scandal involving Wedtech Corporation In Re Wedtech. Sec Litig., M 21-36 (LBS) MDL 735 (S.D.N.Y.), a consolidation of the securities class action with individual cases brought by institutional investors. The actions were settled on the eve of trial in 1992 after 6 years of heavy litigation against two accounting firms, two underwriter  firms, a law firm, and individual defendants for $77.5 million, 50% of damages, one of the then largest settlements in a securities fraud action.  Ms. Rosner also has extensive experience under the Employee Retirement Income Security Act (ERISA), and has been involved as co-lead counsel in several ERISA cases. Ms. Rosner's cases, both prior to and subsequent to the enactment of the Private Securities Law Reform Act ("PSLRA"), have involved complex securities litigation involving accountants, underwriters, law firms, venture capital defendants, as well as complicated factors related to bankruptcies, insurance policies and other related issues.  Many of Ms. Rosner's cases have been litigated intensely until the eve of the trial with the classes recovering a substantial percentage of damages compared to the national average.  She has recovered over a billion dollars for her clients. 

Prior to her retirement in 2016, Ms. Rosner continued to serve as lead or co-lead counsel in numerous other major securities class actions.  Ms. Rosner was the sole chair of the Firm's Securities Litigation Department and the chief attorney at the Firm in charge of the Firm’s representation of its institutional clients which include the States of Mississippi, Georgia, Pennsylvania, Washington, City of San Francisco, and others.  Because of her experience, Ms. Rosner was regularly asked to lecture before panels on continuing legal education as more fully described below.

Following is a sample of the major class actions Ms. Rosner has successfully litigated. 

  • Plumbers’ & Pipefitters’ Local #562 Supplemental Plan & Trust et al. v. J.P. Morgan Acceptance Corp. I et al., 2:09-cv-01713 (E.D.N.Y.) (PKC) (WDW), in which Wolf Popper represented the Public Employees’ Retirement System of Mississippi (“MissPERS”), as lead plaintiff, in an action against JPMorgan Acquisition Corp. (“JPMAC”), certain individuals employed by JPMAC or its affiliates, and JP Morgan Securities, Inc.  The class consisted of investors who purchased certain mortgage pass-through certificates (mortgage-backed securities) across 26 Offerings, with an initial face value of approximately $23 billion.  MissPERS’s consolidated complaint alleges that the offering documents pursuant to which the JPMAC securities were sold contained misrepresentations and omitted to disclose information concerning the underwriting of the mortgage loans serving as collateral for the securities.  The parties engaged in extensive motion practice and discovery.  In February 2012, Lead Plaintiff defeated Defendants’ motion to dismiss in substantial part.  On May 2, 2014, the Honorable Pamela K. Chen entered an order preliminarily approving a settlement that resolved the action for a total of $280 million in cash, stating "it's very clear that this has been a hard fought and well negotiated, seemingly well negotiated, result.  So I think that's kudos to you all certainly better than any kinds of trial I would say."  Subsequently, on July 24, 2014, Judge Chen gave final approval to the settlement, finding that “the representation of both sides was obviously very vigorous. The plaintiffs, I know, expended efforts in terms of pursuing the investigation, the theories, the research and the advocacy.”  The Action “was a difficult case.  Certainly in the beginning, at the time when some of the principals, the legal principles that are applied in this case, in any cases related to mortgage-backed securities, was not well established. They did yeomen's work, I think, in trying to establish some of those principles. . . . [T]his is a good result in this particular case.”  Wolf Popper believes that it is the third largest settlement in a class action against banks that issued mortgage-backed securities.
  • Middlesex Retirement System v. Quest Software, Inc., 527 F. Supp. 2d 1164 (C.D. Cal. 2007); and Middlesex Retirement System v. Quest Software, Inc., CV 06-6863 DOC (RNBx), Amended Order (C.D. Cal. July 10, 2008) (decisions primarily denying defendants’ motions to dismiss in options backdating case). The Court approved a $29.4 million (plus the cost of notice) settlement in the action.
  • In Thurber v. Mattel, Master File No. CV-99-10368-MRP(CWx) (C.D. Cal.) (§10(b) claims) and Dusek v. Mattel, Master File No. CV-99-10864-MRP(CWx) (C.D. Cal.) (§14(a) claims), which were consolidated, Ms. Rosner was a member of the Executive Committee for both cases and led the prosecution of the Dusek v. Mattel §14(a) claims.   After more than three years of extremely hard-fought litigation, including the production of millions of documents and the taking or defending of more than 40 depositions, both cases settled for the aggregate sum of $122 million, with Ms. Rosner achieving a $61 million allocation for the Dusek v. Mattel §14(a) class, believed to be the largest settlement of a §14(a) case.  The Judge specifically found that "Wolf Popper LLP vigorously prosecuted the Dusek action and zealously represented the interests of the Dusek class members." The settlement was affirmed on appeal by the Ninth Circuit Court of Appeals.
  • Ms. Rosner had primary responsibility for Wolf Popper's representation as Special Advisory Counsel to the State of Wisconsin Investment Board in the Anicom litigation (In re Anicom Inc. Sec. Litig. 00-C-4391 (N.D. Ill.)). Wolf Popper conducted the investigation of plaintiffs’ claims, including extensive interviews of Anicom’s former employees and customers, and prepared the initial Amended Complaint.  That complaint was sustained by the District Court, leading to a global settlement, including a substantial contribution from individual defendants. 
  • In connection with the approval of a settlement over the merger of the American Stock Exchange and the NASD in Philipson v. American Stock Exchange, 98 Civ. 4219 (DC) (S.D.N.Y., Transcript of Proceedings, February 18, 1999, at 8-11), the Court complimented the Firm for its "terrific job" in negotiating a "substantial [recovery]."
  • On the eve of trial, Ms. Rosner settled Danis v. USN Communications, Inc., 98 C 7412 (N.D. Ill.). The settlement returned to class members 36% of maximum provable damages in a case where USN was bankrupt and the recovery was obtained against venture capital defendants, insurance covering its members who sat on USN's Board and Merrill Lynch.  The court’s decision denying defendants' motion to dismiss is reported at 73 F. Supp. 2d 923 (N.D. Ill. 1999).

Ms. Rosner has also served as co-lead counsel in cases brought under the Employee Retirement Income Security Act (ERISA), to recover losses to retirement plans and their participants and beneficiaries arising out of plan fiduciaries’ breaches of duty. For example, Ms. Rosner was appointed as plaintiffs’ co-lead counsel in In re AIG ERISA Litigation, No. 04 Civ. 9387 (JES) (S.D.N.Y.), resulting in a $24.2 million settlement.  She served as plaintiffs’ co-lead counsel in In re Citigroup ERISA Litigation II, No. 11 Civ. 7672 (JGK) (S.D.N.Y.), and In re AIG ERISA Litigation II, No. 08 Civ. 5722 (LTS) (S.D.N.Y.), which reslted in a $40 million settlement, with the court stating at the settlement approval hearing that Wolf Popper is “among the premier firms practicing in this area of the law;” that “[Wolf Popper] are themselves very experienced and highly competent securities class action litigators…. [and] are experienced class action litigators [with] strong knowledge of the applicable securities laws and ERISA provisions.” 

Ms. Rosner named on the Super Lawyers  (New York Metro Edition) list from 2007-2015 and was listed as one of the 100 best women lawyers by Super Lawyers in 2014.

Ms. Rosner is a former member of the Federal Courts, Corporation Law, and Securities Regulation Committees of the Bar Association of the City of New York.  She is currently a member of the litigation section of the American Bar Association.  She has written and lectured widely on issues involving securities litigation and accountants' liability and has served on the following panels:

  1. CityBar Center for Continuing Legal Education, The Association of the Bar of the City of New York (New York City Bar Association) "Securities Litigation Current Developments and Strategies", February 2, 2006;
  2. CityBar Center for Continuing Legal Education, The Association of the Bar of the City of New York, (New York City Bar Association) "Prosecuting Securities Class Actions & Derivative Suits", May 13, 2004;
  3. Practicing Law Institute ("PLI") on "Accountants' Liability After Enron", May 20-21, 2002;
  4. Practicing Law Institute ("PLI") Securities Seminar 1998, 1999, 2000;
  5. May 8, 2001 and April 25, 2002 New York City Bar Association Seminar on Securities Litigation;
  6. Professional Liability Underwriting Society, "D&O Liability & Insurance Issues Symposium" (January 22-23, 1998);
  7. ALI-ABA Post Graduate Course in Federal Securities Law: "The Aftermath of Securities Litigation Reform" (July 22-24, 1997);
  8. PLI seminar on Sweeping Reform: Litigating & Bespeaking Caution Under the New Securities Law (1996);
  9. PLI 28th Annual Institute on Securities Regulation (1996);
  10. Federal Bar Council Roundtable: "Private Securities Litigation, A New Life Form Emerges" (October 23, 1996);
  11. PLI seminar on Accountants’ Liability (1988, 1993 and 1994);
  12. Federal Bar Council Roundtable: Ethics and Professionalism in Witness Preparation and Depositions (March 22, 1994);
  13. American Bar Association 1993 summer meeting on the subject of RICO claims against accountants after the Supreme Court decision in Reeves v. Ernst & Young (1993);
  14. April 11, 2002 City Bar Center for Continuing Legal Education, Women in Negotiation: Practical Tips to Strengthen Your Negotiation Skills (For You & Your Clients).