Mark H. Mixon, Jr. is Of Counsel in the New York office of Gibson, Dunn & Crutcher and is a member of the firm’s Litigation and Securities Litigation Practice Groups.
Mark is a general corporate and commercial litigator who represents individual and corporate clients in complex, high-stakes business and corporate governance disputes, including commercial breach of contract actions, corporate-control litigation, disputes related to directors’ and controlling stockholders’ fiduciary duties, stockholder derivative and securities litigation, M&A-related litigation, and antitrust and competition matters. He frequently litigates in the Delaware Court of Chancery, where he clerked for the Honorable J. Travis Laster, the Honorable Tamika R. Montgomery-Reeves, and the Honorable Donald F. Parsons, Jr. Mark has been recognized in Best Lawyers: Ones to Watch in America™ (2024, 2025).
Mark has experience representing companies, boards, and investors across a wide range of industries:
Control Fights and Other Fiduciary Duty Litigation
- Representing consumer tech venture capital firm and director in litigation regarding portfolio company board’s winding up.
- Representing clinical-stage biopharmaceutical company in litigation regarding director and officer compensation.
- Represented independent power producer and control group in confidential arbitrations, securing partial pleading-stage and summary resolutions of disputes with investors regarding valuation and board representation.
- Represented hedge fund and board designees in litigation regarding portfolio company’s allegedly conflicted lending transactions.
- A Shoc Beverage, LLC – Defeated expedited preliminary injunction application in the Delaware Court of Chancery alleging serial entrepreneur and beverage startup breached fiduciary duties by usurping energy drink design and opportunity.
Mergers & Acquisitions and Deal-Related Litigation
- VMware Inc. – Defended cloud computing and virtualization company in Delaware Court of Chancery, obtaining favorable pre-trial settlement of entire fairness claims and post-trial appraisal arising from allegedly conflicted merger transaction with Pivotal Software, Inc.
- South Jersey Industries, Inc. – Represented energy infrastructure company in federal litigations regarding acquisition by private investment fund.
- Slack Technologies, Inc. – Represented software company and its board in federal litigation regarding acquisition by Salesforce, Inc.
- Represented Fortune 200 multinational consumer goods company in indemnification dispute arising from spinoff of healthcare division.
- Vista Outdoor – Represented outdoor sports and recreation products conglomerate in obtaining summary judgment of fraudulent earn-out claims by the founders and sellers of stand-up paddle board company.
Complex Commercial and Antitrust
- Secured temporary restraining order and payment of in-kind success fee on behalf of global law firm.
- Amgen Inc. – Represented multinational biopharmaceutical company in expedited litigation regarding competitor’s breach of settlement agreement and related class antitrust claims.
- Genentech, Inc. – Represented biotechnology company in securing dismissal of contract claims filed by competitor in the Delaware Court of Chancery.
- Empire Merchants, LLC – Represented New York liquor distributor in connection with civil RICO lawsuit against Maryland liquor distributor and related advancement litigation in state and federal courts.
Stockholder Demands and Other Pre-Litigation Matters
- Represented late-stage FinTech company in resolving potential litigation between founders, investors, and financing partner.
- Represented private biotechnology investment fund in avoiding securities and fiduciary duty litigation with majority investor.
- Represented investment banking and capital markets firm in responding to stockholder demand related to merger litigation.
- Represented independent investment banking firm in responding to creditor demands concerning pre-bankruptcy representation of debtor.
- Represented countless companies serving or responding to books and records demands under 8 Del. C. § 220, merger provisions, and operating agreements.
Mark maintains an active pro bono immigration practice. In partnership with Sanctuary for Families, Legal Services NYC, and Immigration Equality, he represents LGBT persons seeking asylum and other forms of immigration relief from U.S. Citizenship and Immigration Services and Immigration Courts. Mark is also a member of Sanctuary for Families’ Pro Bono Council.
Mark is admitted to practice in the State of Delaware and the State of New York, and before the United States District Courts for the District of Delaware, the Southern District of New York, and the Eastern District of New York.
Before joining Gibson Dunn, Mark earned his Juris Doctor magna cum laude in 2015 from the University of Pennsylvania Law School, where he was an executive editor of the University of Pennsylvania Journal of Business Law. He also earned a Master of Education in higher education in 2012 and a Bachelor of Science in Energy Business and Finance in 2011 from the Pennsylvania State University.
Capabilities
Credentials
Education:
- University of Pennsylvania - 2015 Juris Doctor
- Pennsylvania State University - 2012 Master of Education
- Pennsylvania State University - 2011 Bachelor of Science
Admissions:
- Delaware Bar
- New York Bar
Clerkships:
- Delaware Court of Chancery, Hon. Travis Laster, 2021
- Delaware Court of Chancery, Hon. Tamika Montgomery-Reeves, 2015 - 2016
- Delaware Court of Chancery, Hon. Donald F. Parson Jr, 2015