Daniel J. Thomasch is a litigation partner in Gibson, Dunn & Crutcher's New York office, and Co-Chair of Gibson Dunn's Life Sciences Practice Group.  Mr. Thomasch represents clients in complex, high-value cases spanning a broad array of practice areas.  

Mr. Thomasch is a Fellow of the American College of Trial Lawyers, and serves as Vice Chair of the College's Federal Rules of Evidence Committee.  Mr. Thomasch has tried cases to verdict in federal and state courts in New York, Delaware, Maryland, Virginia, Tennessee, Florida, Colorado, Texas and Nebraska.  Mr. Thomasch's appellate experience includes oral arguments in the United States Court of Appeals for the Second, Third, Sixth, Ninth, Eleventh and Federal Circuits and the highest courts of New York, Georgia and Maryland.  Mr. Thomasch is regularly asked to assume lead responsibility for ongoing matters in which developments such as unfavorable pretrial rulings have significantly increased the stakes of the litigation and/or diminished the likelihood of success at trial, and he has a record of consistent success in those situations.

Mr. Thomasch has been recognized by  Lawdragon as among the "Top 500 Lawyers" and as one of the "500 Leading Litigators."  He was named an "IP Star" by Managing Intellectual Property magazine, and a "Life Sciences Star" in the inaugural publication of LMG Life Sciences 2012, and in each subsequent issue.  Chambers USA:  America's Leading Lawyers for Business has repeatedly ranked Mr. Thomasch nationally for Product Liability and Mass Torts, and in New York for Intellectual Property."  Mr. Thomasch is also named by The Best Lawyers in America© as a leading attorney for Product Liability Litigation, and has been named "A Super Lawyer" by Law & Politics every year since 2006 for both product liability defense and intellectual property litigation He is recommended for "Life Sciences:  Product Liability" in PLC's Which Lawyer?; and Benchmark Litigation:  The Definitive Guide to America's Leading Litigation Firms and Attorneys has named him a "Litigation Star" nationally for Products Liability and in the State of New York for Commercial Litigation.  In addition, Mr. Thomasch is ranked by IAM Patent 1000 in patent litigation.

Mr. Thomasch serves on the Steering Committee of the Defense Research Institute's Drug and Medical Device Committee.  He is a member of the American Bar Association, the American Intellectual Property Law Association, the New York Intellectual Property Law Association, the Federal Bar Council and The Association of the Bar of the City of New York (Thurgood Marshall Award, 1998).

Prior to joining Gibson Dunn, Mr. Thomasch was a litigation partner of Orrick, Herrington & Sutcliffe LLP, where he had served as Managing Director of its Litigation Division, Chair of its Life Sciences Industry Group and a member of the firm's Executive Committee.

Mr. Thomasch received his J.D. from Columbia University School of Law in 1981, where he was a Harlan Fiske Stone Scholar and recipient of the Young B. Smith Award.  His undergraduate degree is from Northwestern University.  After law school, Mr. Thomasch was a law clerk to the Honorable Thomas P. Griesa of the United States District Court for the Southern District of New York.

The following is a representative sample of Mr. Thomasch's cases.*

Patent Litigation

  • Trial and appellate counsel for a U.S. mobile phone carrier in a patent infringement jury trial in the District of Nebraska.  After a multi-week trial, the jury returned a complete defense verdict, finding all five accused networks to not infringe any of the six asserted patent claims.  On appeal, the Federal Circuit dismissed Plaintiff's appeal as moot based on its conclusion that the asserted patents recited patent-ineligible subject matter under 35 U.S.C. § 101, as argued by Mr. Thomasch on the carrier's cross-appeal.   
  • Obtained a defense verdict of non-infringement and invalidity on all asserted claims against U.S. mobile phone carrier in a jury trial in the Eastern District of Texas, after obtaining pretrial rulings dramatically limiting plaintiff's damages claim.
  • Lawson Software:  Lead trial counsel for defendant in a civil contempt case following a plaintiff's verdict of patent infringement and the entry of a permanent injunction by the United States District Court for the Eastern District of Virginia.  Developed trial and appellate strategies for the contempt proceedings that resulted in a complete victory on the contempt charge and vacatur of the underlying injunction.
  • Dow AgroSciences (DAS):  Served for more than a decade as lead national trial and appellate counsel on all patent infringement actions against DAS involving patents for making genes and inserting them into plants to make the plants insect-resistant.  Devised and implemented a global litigation strategy that successfully defended (through trial verdicts, summary judgment rulings, voluntary dismissals and appellate rulings) DAS's core business in multiple interrelated patent litigations throughout the United States.  Mr. Thomasch first-chaired and won a bet-the-company jury trial in the District of Delaware in which DAS prevailed against a competitor asserting patent claims that were alleged to cover all transgenic corn products, both commercial and pre-market, in the United States.  He won a qui tam suit against DAS in which plaintiff alleged false marking under 35 U.S.C. § 292.  Mr. Thomasch also argued appeals before the Federal Circuit in multiple cases involving patents asserted by and against DAS, and DAS prevailed in each such appeal.*
  • Alcon Laboratories:  Successfully defended Alcon in multiple patent litigations involving prescription drugs used for lowering intraocular pressure in patients suffering from glaucoma, including summary judgment in a case of first impression involving method claims and alleged off-label uses of prescription drugs; argued and won appeal of that ruling in the Federal Circuit.*
  • Storz Ophthalmics Company:  Obtained dismissal of multiple patent infringement actions involving the design of intraocular lenses and methods for their surgical implantation.*
  • Praxis Biologics, Inc.:  Successfully defended American Cyanamid Company and Praxis Biologics, Inc. at trial in a patent infringement action related to human infant vaccines against bacterial infections such as meningitis.  Trial verdict upheld on appeal to the Federal Circuit.*
  • American Cyanamid Company:  Lead trial counsel in two bench trials in the District of Colorado arising out of an inventorship dispute with associated claims for copyright infringement and common law torts.*

Product Liability and Mass Torts

  • Wyeth:  Served as national lead trial and appellate counsel in nearly 400 product liability cases involving claims that childhood vaccines containing the preservative thimerosal caused autism in vaccinated children, prevailing in every case.  Successfully tried a two-week Frye hearing in which Wyeth attacked all causation theories purporting to link vaccines to autism, resulting in the exclusion of all of plaintiffs' expert witnesses.  Argued the appeal to Maryland's highest court and obtained a unanimous affirmance, which effectively adopted a new standard for the admissibility of expert testimony in civil cases, Blackwell v. Wyeth, 408 Md. 575, 971 A.2d 235 (2009).  That decision resulted in the dismissal of the claims of all of the approximately 300 plaintiffs in cases then-pending against vaccine manufacturers in Maryland.  Devised federal preemption strategy that ultimately resulted in the successful conclusion of the national litigation, argued preemption motions and appeals in state and federal courts, leading to the Supreme Court's decision in Bruesewitz v. Wyeth, in which the Court held that all design defect claims involving recommended childhood vaccines are preempted by the National Childhood Vaccine Injury Act of 1986.*
  • The Dow Chemical Company:  Obtained dismissal of claims brought on behalf of up to thousands of Brazilian citizens seeking damages under the Alien Tort Statute and state law for alleged injuries from environmental contamination.  In another case, Mr. Thomasch obtained dismissal of state law claims brought by more than 300 residents of Ecuador alleging personal injuries from exposure to a commercial fungicide used on banana crops.*
  • Breg, Inc.:  As appellate counsel, obtained reversal of intentional concealment verdict in the California Court of Appeal, resulting in vacatur of a significant punitive damages award and a dramatic reduction in compensatory damages. 
  • American Home Products Corporation:  First-chaired and won the first jury trial of a case involving alleged neurological injuries from the use of the Norplant System, a contraceptive implant, obtaining a complete defense verdict.  Obtained dismissal of numerous cases involving prescription drugs, biologics, medical devices and OTC products, through successful motion practice.*
  • American Cyanamid Company:  Successfully defended litigation initiated by the City of New York to recover for property damage and personal injuries alleged to have resulted from exposure to lead pigment-in-paint manufactured by a putative predecessor-in-interest to Cyanamid.*
  • Lederle Laboratories:  First-chaired and won three multi-week jury trials of cases involving permanent injuries to infants allegedly resulting from immunization with the whole-cell DTP vaccine.  Argued and won the resulting appeals in the United States Courts of Appeal for the Second, Sixth and Eleventh Circuits.*
  • Lederle Laboratories:  Obtained summary judgment prior to class certification of a statewide consumer class action involving a popular multi-vitamin, Caltrate®.*
  • Kidde & Company:  Jury verdict of no liability, despite the jury being instructed that defendant was negligent per se

ERISA Litigation

  • PricewaterhouseCoopers LLP ("PwC"):  As successor counsel, Mr. Thomasch recently obtained judgment on the pleadings for PwC (and successfully opposed Plaintiffs' motion for summary judgment) in a massive, 11-year old ERISA class action pending in the Southern District of New York, in which Plaintiffs sought to compel payment of "whipsaw claims" exceeding $1 billion. 

Employment Litigation

  • PricewaterhouseCoopers LLP (PwC):  Mr. Thomasch is lead trial and appellate counsel for PwC in multiple wage-and-hour class actions.  Mr. Thomasch argued and won the Ninth Circuit appeal of an issue of first impression under the California Labor Code, obtaining reversal of the District Court's summary adjudication in favor of a class of approximately 2,000 unlicensed accountants.  The unlicensed accountants had been found by the District Court to be covered by the overtime provisions of California's wage-and-hour laws as a matter of law, on grounds that would have also applied to professions such as law, medicine and architecture.  Mr. Thomasch was brought in to argue PwC's appeal, and he persuaded the United States Court of Appeals for the Ninth Circuit to reverse the District Court, ruling unanimously in PwC's favor on all issues, leading to a highly-favorable class settlement.

Insurance Coverage Litigation

  • Wyeth:  Served as lead counsel in numerous insurance coverage litigations in which the policyholder sought payment of defense costs incurred in the defense of mass tort litigation, and defense and remediation costs for scores of environmental clean-up sites throughout the country.  Obtained hundreds of millions of dollars of coverage in highly favorable settlements.  Mr. Thomasch has also successfully litigated business interruption claims, claims for coverage under D&O policies and reinsurance disputes.*
  • John Wyeth & Brother:  Served as lead counsel in an insurance coverage action over defense costs incurred by Wyeth in the defense of Benzodiazepine product liability litigation.  Worked closely with barrister and instructing solicitors in the successful trial of Wyeth's claims in the Commercial Court of London.*

Other Litigation and Counseling

  • Mr. Thomasch has also litigated criminal and civil antitrust, securities, RICO, breach of contract, fraud, trade secret misappropriation, breach of fiduciary duty, and replevin cases.
  • Mr. Thomasch has substantial experience counseling corporate clients on potential product liability risks arising out of the introduction of new products to market or the acquisition of product manufacturers or specific product lines.

*Representations occurred prior to attorney's affiliation with Gibson Dunn.


  • Columbia University - 1981 - Juris Doctor
  • Northwestern University - 1978 - Bachelor of Arts


  • New York Bar