Christopher T. Casamassima


Chris Casamassima is a trial lawyer who focuses on complex business disputes. Over the course of his more than twenty-three year career, Chris has handled cases for defendants and plaintiffs involving breach of contract, business torts, fraud, antitrust, trade secrets, environmental claims and many other commercial issues across a variety of industries. Mr. Casamassima aggressively represents his clients, whether litigating a business-to-business contract dispute or defending a company against a class action, mass tort proceedings or qui tam claims. He has been named as one of the Lawdragon 500 Leading Litigators in America, recognized in The Legal 500 United States, and included as a Southern California “Super Lawyer” or “Rising Star” nineteen times. He has also been named to the Los Angeles Business Journal’s “Thriving in their 40s” list, twice nominated by the Los Angeles Business Journal as a Leader in Law, and was recognized by the Daily Journal in 2015 as one of the top twenty lawyers under the age of forty in California.

Professional Activities

Mr. Casamassima is active in the American Bar Association's Antitrust Law and Environment, Energy, and Resources Sections, and has served as a vice chair of the Agriculture and Food, Distribution and Franchising, and Cartel and Criminal Practice Committees of the Antitrust Section. Mr. Casamassima is also a member of the State Bar of California's Antitrust and Unfair Competition Law and Litigation Sections, the California Lawyers Association’s Environmental Law Section, the Italian American Lawyers Association, and the Association of Business Trial Lawyers. Mr. Casamassima has also served on the Board of Directors of the Western Center on Law & Poverty.  



    • Defending environmental engineering contractor in coordinated action involving a class action, mass actions involving over nine thousand individual plaintiffs, qui tam claims and other coordinated civil actions brought in connection with the clean up of Hunters Point Naval Shipyard  
    • Won summary judgment for pharmaceutical manufacturer in qui tam litigation concerning alleged fraudulent claims submitted to insurers
    • Won summary judgment for medical device manufacturer in qui tam litigation concerning alleged fraudulent claims submitted to insurers
    • Defended individuals in connection with claims of improper disposal of hazardous chemicals at the Santa Susana Field Laboratory
    • Successfully represented Theranos in class action alleging fraud and other causes of action based on allegations that its blood-testing technology was flawed
    • Trial counsel in two-week federal jury trial for individual and corporate defendants against SEC where SEC alleged multiple counts of securities fraud
    • Secured $26.5 million settlement for a group of private investors for multiple banks' fraud, breach of fiduciary duty, and aiding and abetting fraud and breach of fiduciary duty in connection with the Reed Slatkin Ponzi scheme
    • Successfully defended Native American tribe against fraud and RICO claims in connection with negotiation of gaming compact
    • Obtained successful confidential settlement on behalf of a group of Taiwanese banks who brought claims for fraud, aiding and abetting fraud, and aiding and abetting breach of fiduciary duty in connection with the collapse of PEM Group
  • Business Torts, Breach of Contract and Financial Services Disputes

    • Won total victory for nation’s largest donor-advised fund after two-week federal bench trial where plaintiffs alleged fraud and negligent securities trading 
    • Obtained dismissal, affirmed by the Ninth Circuit, of breach of fiduciary duty claims against donor-advised fund brought by donor in connection with pool performance and investment selection
    • Won directed verdict for major aerospace company at the close of plaintiff's case in a dispute concerning the pricing of the F/A-18 aircraft
    • Won arbitration award for a satellite manufacturer in an international arbitration where claimant insurance companies alleged claims in subrogation for breach of contract in connection with the loss of a satellite
    • Won arbitration award on behalf of production company for full amount of damages sought—plus fees, costs and interest—for breach of agreement to distribute full-length motion picture in Latin America and Brazil
    • Won jury verdict on behalf of an aircraft systems company against a security and aerospace company for intentional interference with prospective economic advantage arising out of a teaming relationship to upgrade the B-1B bomber's mission computer
    • Won $1 million-plus restitution award for financial services company for amounts expended on attorneys' fees in connection with investigation into alleged insider trading by employee
    • Successfully represented fintech platform in contract dispute with investment funds over funds’ non-payment of profit fee
    • Successfully defended major movie studio in federal and state court class actions brought in connection with a well-publicized data breach
    • Won dismissal of action against director of medical technology company in action alleging breach of fiduciary duty for alleged improper dilution of company's stock
    • Won dismissal of claims relating to alleged trafficking in Cuban property brought under the Helms Burton Act on behalf advertising and public relations firm
    • Defeated actions for preliminary and permanent injunctive relief filed against standardized test provider on behalf of students whose AP test scores were invalidated after discovery of testing irregularities
    • Secured confirmation of arbitration award of more than $5 million for Spanish claimant in an arbitration regarding a cosmetics distribution contract
    • Successfully defended financial services company in action alleging copyright infringement and breach of contract based on alleged overdeployment of software brought by software company
    • Successfully represented social media company in breach of contract claim to enforce its platform’s terms of use
    • Successfully defended developer of successful video game franchise in licensing dispute involving fraud and breach of contract claim
    • Trial counsel for major defense contractor in two-week federal trial over dispute with supplier over the procurement of computer equipment
    • Representing plaintiff shipping and logistics company in California federal court bringing claims for trade secret misappropriation, breach of contract, fraud, and other torts 
  • Antitrust

    • Defending client against Clayton Act § 7 putative class action claim challenging combination of brokerage services providers
    • Successfully defended public utility against monopolization and other antitrust and tort claims brought by solar panel company
    • Successfully defended major movie exhibitor in federal and state actions where other exhibitors allege unlawful clearance agreements and purported circuit dealing in violation of the Sherman Act and state laws
    • Obtained dismissal of complaint for a direct broadcast satellite television company, where plaintiffs alleged Sherman Act claims on behalf of a putative class seeking to require satellite and cable providers to offer a la carte distribution; obtained affirmance from the Ninth Circuit
    • Obtained dismissal of monopolization and misappropriation of trade secrets claims brought by one California law school against another law school operating in the same area
    • Represented clients in Department of Justice investigations and civil class action litigation concerning alleged price fixing and collusion; non-confidential matters include: In Re DRAM Antitrust Litigation; Brookshire Bros. et. al. v. Chiquita Brands International, Inc., et. al.; In Re Marine Hose Antitrust Litigation; In Re Flat Glass Antitrust Litigation (II); In Re Food Service Equipment Hardware Antitrust Litigation; Rigo v. Kason Industries, Inc., et. al.; In Re Transpacific Passenger Air Transportation Litigation; and In Re Air Cargo Shipping Services Antitrust Litigation


  • Recognized as one the Lawdragon 500 Leading Litigators in America (2022-2023)
  • Recommended in The Legal 500 United States (2020)
  • Nominated by the Los Angeles Business Journal as a Leader in Law (2021)
  • Named to the Los Angeles Business Journal's “Thriving in Their 40s” list (2020)
  • Highlighted in Litigation Daily’s “Litigator of the Week” for winning a trial for donor-advised fund sponsor in a closely-watched case regarding the operation of donor-advised funds (March 2021)
  • Included in the Daily Journal's “Top 20 Under 40” in California list (2015) 
  • Named a Super Lawyer or Rising Star in the Southern California Super Lawyers (19 years)
  • Life Fellow of the American Bar Foundation.

Insights & News


  • Education

    • JD, University of California, Los Angeles, School of Law, 2000

      Submissions Editor, UCLA Entertainment Law Review
    • BA, History, University of Pennsylvania, 1997

      magna cum laude
  • Admissions

    • California

    • District of Columbia



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