John I. Coster IV

Senior Associate

  • John I. Coster IV
  • Phone: +1 212 404 8737

    Import to Address Book

  • Duane Morris LLP
    22 Vanderbilt
    335 Madison Avenue, 23rd Floor
    New York, NY 10017-4669
    USA

John I. Coster IV is a senior associate in the New York office and a member of Duane Morris’ Trial Practice Group. Mr. Coster concentrates his practice in the areas of complex commercial litigation, including securities, contract disputes, banking, class actions, business torts, defamation, employment, internal investigations, and regulatory enforcement matters.

Mr. Coster has broad experience representing financial institutions, corporations, investment advisors, real estate developers, media conglomerates, insurance companies, startups, and individuals, in federal and state courts, as well as arbitration. In addition, he represents broker-dealers and financial advisors in industry and customer dispute arbitrations, and enforcement actions before FINRA.

Mr. Coster is a 2015 graduate of St. John’s University School of Law, where he was the Editor-in-Chief of the St. John’s Journal of International & Comparative Law and the New York International Law Review. During law school, Mr. Coster served as a judicial intern to the Honorable P. Kevin Castel of the U.S. District Court for the Southern District of New York. He is a 2012 graduate of Fordham University.

Areas of Practice

  • Commercial Litigation
  • Financial Institution Litigation
  • Broker-Dealer Representation
  • Securities Litigation
  • Labor and Employment Law

Admissions

  • New York
  • New Jersey
  • U.S. District Court for the Southern District of New York
  • U.S. District Court for the Eastern District of New York
  • U.S. District Court for the District of New Jersey

Education

  • St. John's University School of Law, J.D., 2015
    - Editor-in-Chief, St. John's Journal of International & Comparative Law
  • Fordham University, B.S., 2012

Experience

  • Duane Morris LLP
    - Senior Associate, 2025-present
    - Associate, 2020-2024
  • Satterlee Stephens LLP
    - Associate, 2015-2020

Professional Activities

  • New York American Inn of Court

Honors and Awards

  • Named to Best Lawyers "Ones to Watch," 2026

Civic and Charitable Activities

  • Volunteer Soccer Coach

Representative Matters

  • Represented leading food and beverage company in class action related to allegedly deceptive labeling and advertising. Obtained full dismissal of all claims at motion to dismiss stage after oral argument.

  • Represented real estate development firm in contractual dispute with service operator and adjoining landowner related to their unreasonable withholding of consent of proposed financing on client’s multifamily site. The matter settled on terms favorable to the client, after two days of hearings.

  • Represented publishing and global education tech company in class action challenging payment of author royalties for electronic works. Negotiated class-wide settlement.

  • Represented investment bank in suit claiming defendant breached a contract to pay $12 million in fees for services rendered in connection with defendant’s merger with a special-purpose acquisition company.

  • Represented investment bank in suit alleging employment discrimination and retaliation claims. After compelling arbitration in the S.D.N.Y., obtained arbitration award denying all claims. Following confirmation of the award, on appeal the Second Circuit affirmed District Court’s decision to compel arbitration and affirmed the confirmation of the award.

  • Defeated class certification on behalf of rating agency subsidiary in class action alleging violations of the Fair Credit Reporting Act.

  • Represented financial services firm in FINRA investigation related to trading activity and various disclosures made by individual brokers and the firm.

  • Represented investment bank in fee dispute resulting from company’s failure to pay transaction fee after investment bank advised company on certain security offerings, including equity linked securities.

  • Represented AI company in breach of contract and business tort claims in proceedings before the AAA and New York Supreme Court. Successfully negotiated favorable resolution before discovery.

  • Represented publicly traded broadcasting and digital media company in employment discrimination and retaliation suit in the District of New Jersey. The case settled while summary judgment was pending.

  • Represented board of directors in suit challenging a board election. The Court denied the plaintiffs’ preliminary-injunction application and dismissed their complaint in its entirety, thereby upholding the propriety of an annual meeting to be held pursuant to an emergency COVID amendment to N.Y. Not-for-Profit Corporation Law Sec. 603(a).

  • Represented real estate developer and executives in the Southern District of New York in defense of multimillion RICO claims related to real estate projects.