Denise L. Plunkett

Tel 646.346.8036
Fax 212.223.1942
New York

Denise L. Plunkett is a partner in the firm’s Antitrust and Competition, Loss Recovery, and Consumer Financial Services practice groups. During her 25+ year career, Denise has handled an impressive array of high-profile litigations, including antitrust cases and other types of high-stakes commercial disputes. An experienced trial attorney, she represents corporate clients on both sides of the “v.”, in affirmative litigation and in defending direct and class actions.

Denise has significant experience in the payments, financial services, and pharmaceutical industries, and has led the firm’s Payments Industry Group. She has longstanding relationships with leading companies in the payments and banking sectors. She is a trusted advisor to her clients, aggressively representing them in litigation, providing antitrust and regulatory guidance, and helping them to navigate issues related to legal and conduct risk. Her diverse litigation and counseling practice includes trials and appearances in numerous federal and state courts, international and AAA arbitrations, advocacy before the FTC Bureau of Competition, appellate and other post-judgment representations. In her loss recovery practice, she partners with clients to identify cost-effective ways to protect and recover corporate assets while remaining sensitive to business relationships.

Denise is a recognized Firm leader. She was a Managing Partner of the New York Office and member of Ballard Spahr’s Expanded Board from 2015-2020. She is passionately involved in Diversity & Inclusion, including as a national Co-Chair of Ballard Women from 2017-2020, which aims to recruit, retain, and promote female attorneys throughout their legal careers. She maintains an active pro bono practice, and has served on the firm’s Associate Evaluation and Compensation Committee. Denise was selected for Ballard’s inaugural Leadership Development Program for partners in 2019.

Denise Co-Chairs the New York State Bar Association’s Unilateral Conduct Committee and is a member of the New York City Bar Antitrust Committee. She regularly speaks and writes in a wide variety of areas, including antitrust developments, litigation practice, gender diversity in the profession, and ethics. In 2020, she was ranked in The Legal 500 for Antitrust - Civil Litigation/Class Action – Plaintiff, in recognition of her work representing corporate plaintiffs in high-profile antitrust litigations.

Representative Matters


  • International Cards Co. v. Mastercard International Incorporated (S.D.N.Y. 2017) (2d Cir. 2018). Successfully represented Mastercard in jury trial of claims and counterclaims arising out of Mastercard’s termination of plaintiff’s Mastercard membership. Successfully defended Second Circuit appeal of judgment in favor of Mastercard. Plaintiff sought over $90 million in damages.
  • In re Currency Conversion Fee Antitrust Litigation, 265 F. Supp. 2d 385 (S.D.N.Y. 2003); In re Currency Conversion Fee Antitrust Litigation, 361 F. Supp. 2d 237 (S.D.N.Y. 2005). Obtained Rule 12(b)(6) dismissal of Truth-in-Lending Act claim against payment card network; also obtained district court decision enforcing arbitration provisions in cardholder agreements as to payment card network on grounds of equitable estoppel.
  • Schwartz v. Visa Int’l Service Assoc., et al., 2005 WL 237015 (Cal. App. 1 Dist.) (Sept. 28, 2005). Represented MasterCard in six month bench trial under California’s Unfair Competition Law (§ 17200) concerning payment card currency conversion practices. Prevailed on appeal.
  • Paycom Billing Services, Inc. v. MasterCard International, Inc., 467 F.3d 283 (2d Cir. October 27, 2006). Successfully moved to dismiss antitrust claims relating to payment card “chargebacks;” Second Circuit affirmed district court decision dismissing the case.
  • PSW, Inc. v. Visa USA, Inc., No. C.A. 04-347T, 2006 WL 519670 (D.R.I. Feb. 28, 2006). Obtained Rule 12(b)(6) dismissal of antitrust claims relating to, inter alia, chargeback rules and policies.
  • Garner v. Capitol One Bank and MasterCard International, Inc., No. CV-01-BU-0712-S (N.D. Ala. 2001). Obtained Rule 12(b)(6) dismissal of Truth-in-Lending Act and civil conspiracy claims against payment card network relating to alleged unsolicited issuance of cards.


  • In re Liquid Aluminum Sulfate Antitrust Litig. (D.N.J). Representing multiple municipalities and water utilities as plaintiffs in actions claiming that defendants engaged in anticompetitive conduct, including price fixing and bid rigging, in connection with the sale of water treatment chemical.


  • Eisai Inc. v. sanofi-aventis US LLC, et al., 821 F. 3d 394 (3d Cir. 2016). Represented on appeal plaintiff Eisai Inc. in pharmaceutical antitrust case challenging alleged monopolistic conduct in the sale of anticoagulant after District Court granted summary judgment against its claims.
  • Sucampo Pharmaceuticals, Inc. v. Takeda (ICC 2012). Co-lead counsel for U.S. pharmaceutical company and related entities in an International Chamber of Commerce arbitration involving claims for, inter alia, breach of contract based on licensee’s alleged failures to use “best efforts” in commercializing claimants’ FDA-approved product.

Financial Services

  • Zandman v. Citibank, N.A., et al. (S.D.N.Y. 2018). Obtained counterclaim judgment, including attorney’s fees award, in AAA arbitration after prevailing on motion to compel arbitration in Fair Credit Billing Act case.
  • Castle Placement v. Freedom Mortgage, et al. (New York Supreme 2018). Defeated breach of contract and common law claims against mortgage business in “finder’s fee” dispute following acquisition.
  • Van Deventer, et al. v. CS SCF Management, Ltd., et al. (New York Supreme 2010). Represented Credit Suisse entities in a case asserting claims and counterclaims arising out of the termination of investment funds and related agreements. Led negotiation of favorable post-trial settlement.
  • Steele v. WMC Mortgage (N.D. Cal. 2008). Successfully moved for order requiring joinder of third-party mortgage brokers in Equal Credit Opportunity Act and Fair Housing Act putative class action against mortgage lenders alleging discriminatory pricing policies.
  • Klutho v. GE Money Bank (E.D. Mo. 2006). Successfully moved to dismiss claim that a prescreened offer for an open-end line was not a “firm offer of credit” under the Fair Credit Reporting Act.
  • Successfully defended dozens of consumer class and individual actions asserting claims under the Fair Credit Reporting Act, Fair Debt Collection Practices Act, and Fair Credit Billing Act against major payment card issuers and third-party debt collection agencies.


Co-Author, “The Federal Antitrust Laws,” Basri & Kagan, Corporate Legal Developments, Practicing Law in a Corporation, Practising Law Institute (updated annually 2009-2020)

Co-Author, Chapter on Section 2 of the Sherman Act, Antitrust Advisor (updated bi-annually)

Co-Author, Legal Alert, “N.Y. Decision May Hinder Early Class Action Settlements” (January 4, 2018)

Co-Author, Legal Alert, “California Federal Court Rules ‘No Surcharge’ Law Unconstitutional” (April 6, 2015)

Co-Author, Legal Alert, “N.Y. DFS Becomes First State Regulator To Bring Dodd-Frank UDAAP Action” (April 24, 2014)

Co-Author, “Evolving Standards Under Sherman Act Section 2,” ABA Antitrust Section Spring Meeting (Feb. 2013).

Co-Author, “Federal Trade Commission v. Actavis: Supreme Court Holds That Rule of Reason Applies in “Reverse Payment” Patent/Antitrust Case,” Client Alert (June 2013)

Co-Author, “Certain Defenses in Recent Mortgage Lending Cases,” Law Seminars International: Subprime Lending Crisis Conference, New York, NY (March 2008)

Federal Court Upholds Auto Lease Early Termination Formula,” Consumer Financial Services Law Report, New York, NY (November 21, 2002)

Speaking Engagements

Moderator, “Winning the Rare Section 2 Trial,” New York State Bar Association Antitrust Section Meeting, Unilateral Conduct Committee (January 2020)

Moderator, “Hot Topics in NY Antitrust: Class Certification and Fraud-Based Antitrust Investigations,” New York City Bar’s Antitrust & Trade Regulation Committee (April 2018)

Speaker, “Deposition Fundamentals,” Practicing Law Institute, Taking and Defending Depositions, New York, NY (Annual Seminar, 2009 - 2020)

Speaker, Webinar: “New Enforcement Actions by the Old Sheriff in Town: Recent Developments at the Federal Trade Commission” (December 2018)

Speaker, Webinar: “Effective Strategies for Dealing With Debt Settlement Companies” (October 2017)

Speaker, “Common Ethical Issues Faced By In-House Counsel,” Ballard Spahr Antitrust CLE (October 2017)

Speaker, “Fair Lending: Managing and Defending Against Claims of Discriminatory Lending and Assessing the Status of ‘Disparate Impact’ in Lending Litigation and Enforcement,” American Conference Institute: Residential Mortgage Litigation and Lending (Sept. 2012)

Speaker, “Consumer Protection Litigation Update,” WG&M Consumer Financial Services High Stakes Symposium, New York, NY (May 2007); San Francisco, CA (September 2006); Dallas, TX (May 2006); New York, NY (2005)

Speaker, “Arbitration Agreements and Class Actions,” West Legalworks Class Actions Conference, New York, NY (November 2006)

Speaker, “Payment Card Litigation Update,” 20th Annual Payment Card Institute, Arlington, VA (May 2006)

Speaker, “Arbitration Agreements and Unconscionability Defenses,” Thomson LegalWorks Class Action Conference, New York, NY (December 2005)

Rankings and Recognitions

The Legal 500, Antitrust - Civil litigation/class action – plaintiff, 2020

Boston University School of Law (J.D. 1994, cum laude)
Probate and Family Law Journal
G. Joseph Tauro Scholar; Recipient
Prentice Hall Book Award in Federal Taxation
ATLA Mock Trial Competition, National Semi-Finalist

University of Maryland (B.A. 1991)
Dean’s List
Member, Mock Trial Team

New York


U.S. District Courts for the Southern and Eastern Districts of New York

U.S. District Court for the District of Massachusetts

U.S. Court of Appeals for the First Circuit

U.S. Court of Appeals for the Second Circuit

U.S. Court of Appeals for the Third Circuit