David De Bruin is a seasoned first-chair trial and appellate attorney. He concentrates his practice on patent litigation and related proceedings before the United States Patent and Trademark Office and also litigates patent malpractice matters. David successfully argues legal issues, as well as explains complex technology to judges and juries.

  • Tries patent cases in a variety of venues before judges and juries and has successfully argued numerous patent cases before the Federal Circuit Court of Appeals
  • Represents clients in a wide array of technology ranging from mechanical and electrical devices to biological and chemical patents
  • Serves as an arbitrator deciding securities claims and IP insurance coverage issues
  • Provides testimony as a Markman expert
  • Authors patent opinions and provides IP counseling



Representative Matters

  • Prepared an amicus brief whose arguments were noted in a recent en banc ruling
  • Obtained a liability jury verdict in the Central District of California on a patent covering 3D computer modeling that lead to a recovery publicly valued in excess of $90 million
  • First-chaired jury trials in the rocket docket of the Western District of Wisconsin and, in a last minute substitution of lead trial counsel, obtained a willful infringement finding against Walmart in the District of Colorado
  • First-chaired a five-week long accountant liability trial that remains a leading accountant liability and attorney misconduct case in Wisconsin
  • Experienced in non-patent business litigation, including securities fraud, RICO, and telecommunications fraud
Representative Cases
  • Gemtron Corp. v. St. Gobain Corp. 572 F.3d 1371 (Fed. Cir. 2009); counsel for patentee plaintiff-appellee. Judgment for plaintiff affirmed.
  • Ormco Corp. v. Align Technologies, Inc. Case No. SACV 03-16 CAS (C.D. Ca. 2009), remanded from 498 F.3d 1307 (Fed. Cir. 2007), cert. denied 128 S.Ct. 2430 (2008); counsel for plaintiff- appellant Ormco on patents regarding computerized design and manufacturing of custom orthodontic appliances. Initial dismissal reversed in part on claim construction and affirmed as to cross-appeal. Upon remand, jury verdict for plaintiff. Settled thereafter for cash and stock valued at $90 million plus additional consideration.
  • Ormco Corp. v. Align Technologies, Inc. 463 F.3d 1299 (Fed. Cir. 2006); counsel for counterdefendant-appellant on patent claims. Summary judgment for counterplaintiff-appellee reversed and claims held obvious.
  • Golight Inc. v. Wal-Mart Stores, Inc. 355 F.3d 1327 (Fed. Cir. 2004), aff’g 216 F. Supp. 2d 1775 (D. Colo. 2002); appeal and trial counsel for plaintiff-appellee patent owner. Judgment of willful infringement affirmed.
  • Bemis Mfg. Co. et al. v. Dornoch Med. Sys., Inc. Nos. 00-1585, 01- 1007 (Fed. Cir. 2001); counsel for plaintiff-appellant in action involving devices and methods for disposing of medical suction canister waste. Summary judgment for defendant reversed based upon error in claim construction.
  • Johnson Worldwide Associates v. Zebco, et al. 175 F.3d 985 (Fed. Cir. 1999); plaintiff-appellee’s counsel on patent regarding heading lock for trolling motors. Summary judgment for plaintiff affirmed.
  • Marquip, Inc. v. Fosber America, Inc. 198 F.3d 1363 (Fed. Cir. 1999), aff’g unpub. dec. and 30 F. Supp. 2d 1142, (W.D. Wis. 1998), upon remand from 155 F.3d 567 (Fed. Cir. 1997); counsel for defendant-appellee in patent infringement action concerning corrugated paperboard machinery. Summary judgment of no infringement affirmed.
  • 3M Company v. Kerr Corporation Case No. 07-C-0087-C (W.D. Wis. 2007); counsel for defendant in action for infringement of patents claiming composites and methods for making the same.
  • Briggs & Stratton Corp. v. Kohler Co. 408 F. Supp.2d 697 (W.D. Wis. 2006), 405 F. Supp.2d 986 and 398 F. Supp.2d 974 (2005); counsel for plaintiff in action for infringement of patents covering engine balancing system and cylinder head. Defendant enjoined following motions after trial.
  • Kerr Corporation v. 3M Company et al. Case No. 06-C-0423-C (W.D. Wis. 2006); counsel for plaintiff in action for infringement of patents covering apparatus and method for curing material with LED radiation.
  • John Mezzalinqua Associates, Inc. d/b/a PPC v. Corning Gilbert, Inc. Case No. 3-CV-0354-S (W.D. Wis. 2003); counsel for plaintiff in patent infringement action involving coaxial cable connectors. Jury verdict for plaintiff.
  • Zeevi v. Robert Bosch Corp. (N.D. Ill. 2003); counsel for defendant in action for infringement of patents covering vehicle navigation system.
  • Trombetta LLC v. Dana Corp. (W.D. Wis. 2003); counsel for defendant in action for infringement of patents covering solenoid switches.
  • The Toro Company et al. v. Scag Power Equipment (D. Neb., 2001); counsel for defendant in patent infringement action involving commercial lawn mowers.
  • Williams et al v. University of British Columbia et al. No. 00-485-A (E.D. Va. 2000); counsel for plaintiff in action to halt issuance of patent containing confidential technology derived from plaintiff regarding use of liposomes to treat arterial disease.
  • M&Z Produktions und Handelsgesmbh v. Hotronic International, Ltd. et al. (E.D. Va. 1999); counsel for plaintiff in action for fraudulent theft of patent and trademark rights regarding ski boot warmers and for infringement.
  • Ness v. Digital Dial Communs., Inc. 222 Wis. 2d 374; 588 N.W. 2d 63 (1999); counsel for plaintiff class. Judgment for plaintiffs affirmed.
  • Chevron Chemical Co. et al. v. Deloitte & Touche 207 Wis. 2d 43 (1997) upon remand from 176 Wis. 2d 935 (1993), aff’g, 168 Wis. 2d 323 (Ct. App. 1992); counsel for plaintiff in third-party accountant liability action. Judgment for plaintiff affirmed on merits and as sanction.
  • Aetna Cas. & Sur. Co. v. Berson, et al. (E.D.N.Y. filed 1995); counsel for Aetna in RICO fraud action, seeking more than $45 million and naming 48 defendants, and in related satellite actions.
  • McMurray v. Harwood 870 F. Supp. 917 (E.D. Wis. 1994); action for correction of patent inventorship under 35 U.S.C. § 256 involving plastic composite toe-cap patent.
  • In re Texas International Co. (U.S., Bank, W.D. Okla.); counsel for the Official Committee of Equity Security Holders responsible for investigating securities transactions involving Drexel Burnham Lambert and affiliates. Successful objection to $14 million in Drexel claims.
  • State of West Virginia ex rel. Insurance Commissioner as Receiver of Quality Insurance Co. v. Abdallah (D.W.Va.); Commissioner’s Counsel in RICO fraud action against former officers and directors.




Court Admissions



  • The Best Lawyers in America, 2012-2024
    • Recognized in practice areas of:
      • Litigation - Intellectual Property
      • Litigation - Patent
      • Patent Law
  • Illinois Super Lawyers, 2013-2021
  • Law Bulletin Media
    • Leading Lawyers, Intellectual Property Law , 2017, 2022, 2023
    • Leading Lawyers, Patent Law, 2017, 2022, 2023
  • Listed in Chambers USA: America’s Leading Lawyers for Business, 2006-2013
    • Recognized as one of America's leading lawyers in the Litigation field in Illinois and Wisconsin; Chambers USA states:
      • 2012 – "Clients praise David De Bruin for being 'very clear in his explanations in litigation and procedure.' He acts on behalf of clients in patent litigation at trial and appellate level."
      • 2010 – "Another impressive litigator at the firm is David De Bruin…He is noted for his 'superb analytical mind and ability to think his way around any issue.'"
  • The Chicago Tribune and The Wall Street Journal, Named one of Chicago’s Top Rated Lawyers, 2012
  • Wisconsin Super Lawyers, 2005, 2008, and 2010-2012
  • Who’s Who in America
  • Who’s Who in American Law

Professional & Community Involvement

  • American Bar Association
    • Section of Litigation
    • Section of Intellectual Property Law
      • IPL Section Committee 803 – Resolutions, Co-chair, 2006-2009
      • IPL Section Committee 606 – Experts, Co-chair, 2004-2005
      • IPL Section Committee 602 – Arbitration and other Alternative Procedures, Chair, 2002-2004
      • IPL Section Committee 651 – Special Committee on Attorney Opinions, Chair, 2000-2002
  • American Intellectual Property Law Association
  • Federal Circuit Bar Association
  • International Association for the Protection of Intellectual Property
  • Bar Association of the Seventh Federal Circuit
  • Wisconsin Intellectual Property Law Association
    • Board of Directors, Former Member
  • Richard Linn American Inn of Court
  • Wisconsin Consumer Anti-Fraud Fund, Milwaukee Foundation
    • Advisory Board
  • Legal Aid of Milwaukee, Inc.
    • Board of Directors, Former Member
  • The Executives' Club of Chicago
  • Milwaukee Youth Symphony Orchestra, Inc.
    • Board of Directors, Former Member
  • Milwaukee Public Schools
    • Board of Directors, Former Member
  • Public Policy Forum
    • Education Committee, Former Member
  • MIT Club of Wisconsin
    • Board of Directors, Former Vice President
  • MIT Education Council
    • Former Member
  • Hunger Task Force of Milwaukee, Inc.
    • Executive Committee

News & Insights


  • A Patent Exhaustion Doctrine for the High Tech Global Economy Age
    Event | New York, NY | | | Speaker


  • Protecting medical device integrity
    Publication | Intellectual Property Magazine | July/August 2017
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