Maynard Cooper & Gale and Nexsen Pruet have agreed to merge on April 1, 2023. Together we will be Maynard Nexsen.

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Maggie's Profile

Maggie is a litigator with an emphasis on complex commercial and financial disputes. She is a Member of Maynard’s nationally recognized Securities Regulation & Corporate Finance Practice.

Representing plaintiffs across the country, Maggie’s litigation experience focuses on matters involving structured products, namely residential mortgage-backed securities (“RMBS”). Through this practice, Maggie has obtained judgments and settlements for her clients in the hundreds of millions. Namely, Maggie was a member of the trial team that represented the Federal Housing Finance Agency, as conservator for Fannie Mae and Freddie Mac, in obtaining an $800 million judgment from Nomura and RBS which was unanimously affirmed by the Second Circuit.

Maggie also has experience in significant public impact litigation. For example, she served as counsel in multiple actions concerning the Public Service Loan Forgiveness Program, including a class action against a student loan servicer and an action against the federal agency tasked with administering the PSLF Program. Maggie also represented environmental clients, pro bono, including a solar advocacy non-profit organization and a utility-scale solar firm in administrative proceedings and federal court.

Prior to Maynard, Maggie practiced in New York City and Washington D.C. with a national litigation firm and a litigation boutique. She also previously worked for the Office of the Tennessee Attorney General in its Consumer Protection Division, focusing on multistate investigations and enforcement actions related to opioids, financial institutions, technology companies, and data privacy.

Maggie earned her J.D., cum laude, from Northwestern University School of Law, where she served on the Northwestern University Law Review. She served as a judicial law clerk for the Honorable Victor Marrero of the U.S. District Court for the Southern District of New York. Before law school, Maggie served as a Teach For America corps member while earning her Master of Education in Teaching (MEdT).

Maggie's Experience

  • Represented the Federal Housing Finance Agency, as conservator for Fannie Mae and Freddie Mac, against the world’s largest banks regarding losses on residential mortgage-backed securities, including serving on the trial team that obtained an $800 million judgment from Nomura and the Royal Bank of Scotland that was unanimously affirmed by the Second Circuit.
  • Represented a trustee in a breach-of-warranty suit that secured a $540 million settlement from GreenPoint Mortgage Funding over $930 million in losses on an RMBS trust.
  • Represented a separate securities administrator in a putback action against the trust’s sponsor regarding defective RMBS.
  • Represented public service workers in obtaining a settlement of a putative nationwide class action lawsuit against Navient, one of the nation’s largest student loan servicers, challenging Navient’s practices with respect to advising borrowers on the Public Service Loan Forgiveness Program.
  • Represented a union and public service workers against the federal agency tasked with administering the Public Service Loan Forgiveness Program.
  • Represented casino developer and operator in defeating a claim for $200 million in trademark license fees and obtaining a ruling that the client could use the trademark without further payments during the license term.
  • Represented, pro bono, Vote Solar before the Utah Public Service Commission to determine the value of solar energy in the state’s net metering program.
  • Represented, pro bono, Cypress Creek Renewables against the Montana Public Service Commission for violations of the Public Utility Regulatory Policies Act.

Maggie's Accolades

  • Best Lawyers “Ones to Watch” in Banking and Finance Litigation (2021)

Maggie's Affiliations and Civic Involvement

  • Federal Bar Council, Securities Litigation Committee
  • Southeastern Women in Financial Services (SWIFS)
  • Nashville Bar Association
  • Tennessee Bar Association

Maggie's Speaking Engagements

  • National Association of Attorneys General, Eastern Region Conference on the Surveillance Economy, October 2021.
  • August 27, 2019: Voices for Good Podcast, “For Back-to-School, We’d Like Some Forgiveness,”


State Bar: New York, Tennessee, Washington, D.C.

U.S. District Court: District of Columbia, New York (Eastern, Northern, Southern), Tennessee (Eastern, Middle, Western)

U.S. Court of Appeals: Ninth Circuit

  • Northwestern University School of Law
    • (2013, J.D., cum laude, Order of the Coif, Associate Editor, Northwestern University Law Review)

  • University of Hawai'i at Manoa
    • (2009, Master of Education in Teaching)

  • Georgetown University
    • (2007, B.S. in Foreign Service, magna cum Laude, Phi Beta Kappa, John Carroll Fellow, Krogh Scholar)


The Honorable Victor Marrero, U.S. District Court for the Southern District of New York

Monday, December 20, 2021


Maynard & Gale (Maynard) is pleased to announce that Margaret “Maggie” M. Siller has joined the Firm’s Nashville office as Of Counsel in the Firm’s growing, nationally recognized Securities and Financial Services Litigation Practice. Ms. Siller is a litigator with experience in a range of areas including complex commercial and...

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