Kenneth R. O'Rourke


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Ken O’Rourke litigates complex cases and high-stakes US and international disputes. As an O’Melveny litigator for over thirty years, he has represented established and emerging companies in class actions and other multi-forum civil litigation, “bet the company” cases, government investigations, and antitrust and intellectual property disputes, including several spanning international boundaries. He is both a California and Washington, DC lawyer as well as a solicitor of the Senior Courts of England and Wales and the Republic of Ireland.

Ken is recognized by leading industry publications. Chambers USA: California Antitrust 2019 reports that he is “a spectacular lawyer” who “takes on large-scale civil and criminal antitrust litigation.” Global Competition Review’s 2016 edition of Who’s Who Legal - Competition, called Ken “one of California’s foremost litigators” and praised him for both his competition and IP experience. In 2019, the publication honored Ken as being among the world’s “Competition Thought Leaders.”

Ken’s legal leadership includes chairing/co-chairing the Antitrust Litigation Forum (2010-present), formerly serving as chair of the California State Bar Antitrust & Unfair Competition Law Section, formerly leading O’Melveny’s Los Angeles litigation practice, and counseling the Board and company executives of a 22,000-employee health insurer while serving as its interim chief legal officer and leading its five-state legal division. 

Highlights of Ken’s recent practice include:

  • Representing leading companies investigated by government enforcers and sued by class action plaintiffs and civil claimants for allegedly participating in international price fixing cartels
  • Representing NextEra Energy in defending antitrust conspiracy and monopolization claims in federal court. All federal antitrust claims were dismissed with prejudice via successful motions to dismiss
  • Defending AT&T and Time Warner through litigation and trial brought by the US Department of Justice seeking to block their merger. The district court approved the merger and the Court of Appeals affirmed
  • Defending US Airways in litigation filed by the US Department of Justice seeking to block its merger with American Airlines. The combined airline is now the world’s largest by some measures. 
  • Representing Alaska Airlines in defending its proposed acquisition of Virgin America over allegations of a substantial lessening of competition in a federal court antitrust action filed by travel agents and air passengers seeking to block the acquisition. The merger was approved
  • Defending SK Hynix Inc., one of the world’s leading semiconductor manufacturers, against a decade-long campaign by a Silicon Valley startup that sought to impose patent royalties worldwide on industry-standard memory chips. The global dispute settled after the Silicon Valley company was sanctioned hundreds of millions of dollars 
  • Serving as a senior leader of a trial team that obtained a complete defense victory from a San Francisco jury against $12 billion antitrust claims 
  • Defending pharmaceutical FTC investigations and defending class actions by plaintiffs alleging anti-competitive “reverse payment settlements” that supposedly delayed generic drug competition

Honors & Awards

  • 2019 Competition “Thought Leader,” Global Competition Review’s WWL
  • Chambers USA, Antitrust - California (Band 2)
  • Chambers Global, Antitrust - USA Cartel (Band 3)
  • The Legal 500, Antitrust
  • Southern California Super Lawyers, Antitrust
  • Who’s Who Legal - The International Who’s Who of Competition Lawyers, Antitrust
  • Irish Legal 100


Bar Admissions

  • California
  • District of Columbia
  • Solicitor, England and Wales
  • Solicitor, Republic of Ireland

Court Admissions

  • US Supreme Court
  • US Court of Appeals, Ninth and Federal Circuits
  • US District Court, Central, Northern, Southern, and Eastern Districts of California, District of Columbia
  • Senior Courts of England and Wales


  • Loyola Marymount University, J.D., 1985:  St. Thomas More Law Honor Society; Editor-in-Chief, Loyola International and Comparative Law Journal
  • University of California, Los Angeles, B.A., 1982

Professional Activities


  • Chair, The Antitrust Litigation Forum (2010-2018); Co-chair (2019)
  • Chair, Executive Committee of the California State Bar Antitrust & Unfair Competition Law Section (2013-14), Vice Chair (2012-13)
  • ABA Antitrust Section’s International Cartel Task Force (2013-2018)
  • Vice Chair, ABA Antitrust Section’s Program Committee (2017-present)
  • Co-Chair (Former) Trade Secrets Subcommittee of the American Bar Association (ABA) Litigation Section’s Intellectual Property Committee
  • Vice Chair, UCLA Department of Neurology Board of Advisors


International Cartel Litigation

  • Speaker, “Can I See That? Discovery Across Borders,” American Bar Association Section of Antitrust Law Global Private Litigation Conference (Berlin, Germany, June 2019)
  • Guest Lecturer, “Extraterritoriality,” The Globalization of Cartel Enforcement, George Mason’s Antonin Scalia Law School (Arlington, VA, April 2019) 
  • Chair & Moderator, “Antitrust Developments in Asia,” Legal Talk Network, an ABA Antitrust Section Podcast (March 2019) 
  • Panel Chair & Moderator, “Global Class Action Developments,” ABA Antitrust Section’s Spring Meeting (Washington, DC, March 2019)
  • Program Chair & Speaker, “Trying Cartel Cases: Effective Strategies for Proving and Defending the Case,” ABA Antitrust Section’s Global Seminar Series (Hong Kong, October 2018)
  • Co-Discussion Leader, “Current Administration’s Approach to Antitrust Enforcement,” The Antitrust Litigation Forum (October 2018)
  • Speaker, “International Price-Fixing Cartels: Dawn Raids, Criminal Investigations & Civil Litigation,” Irish-American Society’s 2018 Law Symposium (Cleveland, OH, September 2018)  
  • Speaker, “Cartel Enforcement Update 2018,” Legal Talk Network (LTN) ABA Antitrust Podcast (August 2018)
  • Roundtable Participant, “Cartel Investigations and Litigation,” Corporate Disputes (July - September 2018 Issue)
  • Panelist, “Private Damages Actions - A New Frontier,” ABA Antitrust in Asia Conference (Seoul, Korea, May 2018) 
  • Co-Discussion Leader, “Parallels Between EU and US Antitrust Law and Practice,” European Forum on Competition Litigation (London, November 2017)
  • Speaker, “Class Certification in Cartel Cases,” IBA/ABA International Cartel Workshop (Tokyo, Japan, February 2016)
  • Panelist, “Sir, please step out of the line - Criminal Cartel Developments,” GCR Antitrust Live - Miami (February 2015) 
  • Co-Discussion Leader, “Convergence of Continuity: Litigating and Settling US Cases with Private Actions Outside the US,” Antitrust Litigation Forum (Napa, California, October 2014) 
  • Co-Author, “Guilty Pleas in Antitrust Civil Litigation,” Antitrust Report (September 2014)
  • Panelist, “Civil Litigation in the Aftermath of Criminal Prosecution: How to Use and Diffuse Guilty Pleas,” ABA Antitrust Spring Meeting (Washington, DC, March 2014)
  • Speaker, “Opting Out of Class Actions in Cartel Cases,” IBA/ABA International Cartel Workshop (Rome, Italy, February 2014) 
  • Panelist, “GCR Live: 2nd Annual Law Leaders Asia-Pacific Conference - Singapore,” Global Competition Review (Singapore, March 2013) 
  • Co-Author, “Reflections on Cartel Enforcement,” ABA Antitrust Magazine - 25th Anniversary Edition (December 2012) (with Ian Simmons) 
  • Discussion Co-Leader, “Antitrust Litigation Trials,” 2012 Antitrust Litigation Forum (Napa Valley, California, December 2012)
  • Moderator, “‘Big Stakes’ Antitrust Trials,” 22nd Annual Golden State Antitrust and Unfair Competition Law Institute (San Francisco, October 2012) 
  • Moderator, “Defense 9, Plaintiff 3: Winning Over the Jurors in the $12 Billion Rambus Antitrust Trial,” Association of Business Trial Lawyers (ABTL) (Orange County, CA, April 2012) 
  • Panel Leader and Panelist, “Internal Investigations,” 2012 ABA International Cartel Workshop (Vancouver, B.C., February 2012) 
  • Moderator and Panelist, “Winning Strategies in U.S. Jury Trials,” In-House Counsel Forum (Seoul, Korea, January 2012) 

Intellectual Property Rights Intersecting Antitrust Law

  • Panelist, “Antitrust and IP Developments for the High Tech Sector,” KNect365 Law’s Antitrust USA: West Coast Conference (San Francisco, February 2019)
  • Co-Author, “Intellectual Property and Antitrust: Getting the Deal Through,” Global Competition Review, USA Chapter (2012-2018) (with Stephen McIntyre)
  • Co-Author, “Promoting Competition and Standards: The D.C. Divide,” ABA Antitrust Section’s Fall Forum (October 2010) (with Julia Schiller)
  • “California Intellectual Property Law Developments,” California Litigation Review (October 2009, October 2010) 
  • Speaker, “Antitrust Laws & Lessons from Standard Setting Organizations,” International Seminar on Anti-Monopoly Issues in the Industry of New and High Technology, China’s Ministry of Industry & Information Technology (MIIT) (Beijing, PRC, June 2010) 
  • Co-Author, “Ashcroft v. Iqbal: The Sleeper 2009 Supreme Court Decision For Patent Litigators?,” Intellectual Property & Technology Law Journal, Vol. 21, No. 12 (December 2009)  

Complex Civil Litigation

  • Co-Author, “‘Off-Ramps’ in US Private Damages Antitrust Actions,” prepared for ABA Antitrust in Asia Conference (April 2018)
  • Co-Author, “Corporations and the Privilege Against Self-Incrimination: Current Issues Under US Law,” prepared for ABA/IBA International Cartel Workshop (February 2018) (with Michael Tubach)
  • Panelist, “Ethics in Joint Defense and Common Interest Groups,” Los Angeles County Bar Association (Los Angeles, California, July 2017)
  • Panelist, “Joint Defense Group Ethics: A Debate & Discussion,” ABA Antitrust Spring Meeting (Washington, DC, April 2017) 
  • Co-Author, “Three Paths to Class Action: Rule 23(b) and the Nature of Class Claims in America,” prepared for ABA/IBA International Cartel Workshop (February 2016) (with Scott Schaeffer)
  • Co-Author, “The Continuing Violations Doctrine: Limitation in Name Only, or a Resuscitation of the Clayton Act’s Statue of Limitations?,” Competition (Spring 2015) (with Stephen McIntyre)
  • Panelist, “Resolving Antitrust Disputes: Arbitration, Mediation, and Settlement,” CLE International Antitrust Law Conference (San Francisco, February 2013)
  • Co-Author, “Preserving Legal Privileges in the U.S., California, and the EU,” Antitrust Report (December 2012) (with Stephen McIntyre & Katelyn Denby)

Pharmaceutical Antitrust Litigation

  • Co-Author, “In re Solodyn Antitrust Litigation: Lessons from a “Big Stakes” Reverse Payment Pharmaceutical Trial,” California’s Journal of Competition (Forthcoming, 2019)
  • Moderator, “Big Stakes Antitrust Trials - In re Solodyn Antitrust Litigation,” California Lawyers’ Antitrust Section Annual ‘Golden State Institute’ (San Francisco, CA November 2018)
  • Co-Discussion Leader, “Healthcare Industry and Pharmaceuticals,” Antitrust Litigation Forum (New Orleans, Louisiana, October 2015) 
  • Co-Author, Drafting Pharmaceutical Patent Settlements With Actavis in Mind, Corporate Disputes Magazine (June 2015) (with Anna Fabish)
  • Panel Chair, “Beyond Reverse Payments: The New Frontiers in Pharmaceutical Antitrust,” ABA Antitrust Spring Meeting (Washington, DC, April 2015) 
  • Co-Author, “New Frontiers in Pharmaceutical Antitrust,” submitted for ABA Antitrust Spring Meeting (March 2015) (with Anna Fabish) 
  • Co-Author, “Patent Validity and Scope Can Be Litigated in Antitrust Suits,” Law360 (Aug. 1, 2014) (with Stephen McIntyre & Ian Simmons)
  • Co-Author, “The Continuing Relevance of Patent Validity in Reverse-Payment Litigation,” Concurrences (May 2014) (with Stephen McIntyre & Ian Simmons)
  • Co-Author, “Viewing FTC v. Actavis Through the Lens of Clayton Act Section 4,” ABA Antitrust Magazine (Fall 2013) (with Ian Simmons & Scott Schaeffer) 
  • Co-Author, “FTC v. Actavis: Reconciling Conflicts In Rules of Reason,” Law360 (July 2, 2013) (with Jon Sallet & Katrina Robson) 

Agricultural Antitrust Litigation

  • Panelist, “The Capper-Volstead Exemptions in an Era of Supply Management and Vertical Integration,” American Bar Association Antitrust State Enforcement, Agriculture & Food, Exemptions & Immunities Committees (September 2012) 
  • Discussion Co-Leader, “The Capper-Volstead Act Exemption and Supply Restraints in Agricultural Antitrust Actions,” New York State Bar Antitrust Section Executive Committee (New York, New York, February 2011)
  • Co-Author, “The Capper-Volstead Act Exemption and Supply Restraints in Agricultural Antitrust Actions,” Competition: The Journal of the Antitrust and Unfair Competition Law Section of the State Bar of California, Vol. 19, No. 2, pp. 69 et seq. (Fall 2010) (with Andrew Frackman) 

Antitrust / Class Actions 

Price fixing

  • Lead counsel defending against numerous direct and indirect purchaser class actions alleging illegal price fixing and/or coordinated supply restraints under federal and state antitrust and unfair competition laws 
  • Lead counsel defending against lawsuits filed by dozens of State Attorneys General on behalf of state and local governments and state citizens (parens patriae) asserting federal and state law claims as direct and indirect purchasers of allegedly price fixed products 
  • Lead counsel defending against large direct action antitrust lawsuits brought by settlement class “opt outs” who purchased billions of dollars of allegedly price fixed or supply restrained products 
  • Trial team member for SK Hynix in defending against a US$12 billion antitrust claim brought by Rambus Inc.; jury verdict for the defense on all claims; recognized as a Top Defense Verdict of 2011
  • Briefed, argued for defense group and twice won dismissal of indirect purchasers’ California Cartwright Act and 13 other state law antitrust claims on the basis of lack of antitrust standing. In re Dynamic Random Access Memory Antitrust Litigation, 516 F. Supp. 2d 1072 (N.D. Cal. 2007) (DRAM I); 536 F. Supp. 2d 1129 (N.D. Cal. 2008) (DRAM II)

Monopolization / Unfair Competition

  • Trial counsel for California electronics firm in federal court jury trials asserting Walker Process / patent misuse and attempted monopolization claims against a dominant international electronics component manufacturer 
  • Counsel for semiconductor manufacturer pursuing monopolization and unfair competition claims in federal court against a semiconductor technology licensing firm charged with abusing a computer industry standard setting process, with related proceedings in the International Trade Commission, Federal Trade Commission, and the European Commission 
  • Counsel for a technology company accused in a series of class actions of violating California state unfair competition laws in connection with the company’ s traffic light photo enforcement services; trial court judgment in favor of our client affirmed by the California Supreme Court 
  • Counsel for a leading international accounting firm charged with RICO and unfair competition in class actions brought by putative classes of all depositors worldwide of a failed international financial institution; federal court's dismissal of plaintiffs’ claims upheld on appeal

Merger Litigation

  • Defending clients AT&T and Time Warner in litigation through trial against the US Department of Justice’s attempt to block the merger in 2017-2018
  • Representing Alaska Airlines in federal court in defending its proposed acquisition of Virgin America in an antitrust action commenced by travel agents and air passengers seeking to block the acquisition in 2016
  • Defending against the US Department of Justice’s lawsuit seeking to block client US Airways’ merger with American Airlines
  • Representing client Humana in defense of litigation by the US Department of Justice seeking to block the merger with Aetna in 2016
  • Defending against the US Department of Justice’s lawsuit seeking to block client T-Mobile’s merger with AT&T

Intellectual Property Litigation

  • Lead trial counsel in federal court proceedings and jury trial in which O’Melveny’s client, the inventor of a computer-controlled artificial respirator, obtained a multimillion-dollar trial court award against a medical device manufacturer for patent infringement and willful patent infringement 
  • Lead counsel representing a then-leading consumer electronics firm in disputes over DVD copyright protection technology, the Digital Millennium Copyright Act and Internet law; also represented the company as lead counsel in multiple business disputes in state and federal courts and in connection with foreign adversarial proceedings 
  • Lead counsel for an aircraft cargo systems manufacturer in successfully pursuing patent infringement claims against an aircraft parts supplier 
  • Trial counsel in trade secret and contract case for a developer of interactive television programming guides and computer software, in which O’Melveny’s client obtained a multimillion-dollar arbitration award 
  • Counsel for a leading computer manufacturer defending against business and technology claims brought by a start-up microprocessor developer for alleged breach of fiduciary duty, breach of contract, and misrepresentation 
  • Counsel in various cases for a large computer/technology OEM defending against patent infringement claims relating to encryption technology for personal computers and to disk drive technologies 
  • Trial counsel for a leading manufacturer of MOSFETs and other semiconductors in a federal court bench trial in connection with a complex patent licensing action

Other Litigation

  • Lead trial counsel representing an insurance company prevailing in a series of state and federal court proceedings and five-week arbitration involving the ownership and lease of a Los Angeles high-rise office building 
  • Lead trial counsel in multiple jury and bench trials serving as Deputy City Prosecutor prosecuting criminal defendants