Photograph of A. Marisa Chun

Government Experience

  • Department of Justice: Office of the Associate Attorney General—Deputy Associate Attorney General
  • Department of Justice: United States Attorneys' Offices—Eastern District of Virginia: Special Assistant U.S. Attorney; District of Maryland: Special Assistant U.S. Attorney
  • Department of Justice: Civil Rights Division—Trial Attorney and Senior Trial Attorney


  • Harvard Law School, J.D., cum laude
  • Yale University, B.A., summa cum laude


  • California
  • District of Columbia

A. Marisa Chun

San Francisco
Phone: +1 415.365.7408
3 Embarcadero Center, 26th Floor
San Francisco, CA 94111

A. Marisa Chun is a partner in the Litigation Group in Crowell & Moring’s San Francisco office. An experienced trial and appellate lawyer, she represents clients in complex commercial litigation, class actions, trials, and appeals, as well as government and internal investigations involving alleged health care fraud, trade secret misappropriation, antitrust violations, sexual misconduct, and other matters.  Marisa focuses on thoughtful advocacy and strategies to secure an early and favorable resolution or victory if the case must be tried.  She has been recognized by The Legal 500, Benchmark Litigation, and Super Lawyers as a leading commercial and white collar lawyer and by The Recorder as a “Woman Leader in Tech Law.”

As a former television reporter, prosecutor, and senior official at the US Department of Justice, Marisa draws upon her legal, government, and media experience when advising clients and boards of directors facing high-stakes matters in today’s highly regulated environment. Bilingual in Korean, Marisa has significant experience advising companies and executives in the Korean technology, life sciences, and energy industries.   

As Deputy Associate Attorney General at the U.S. Department of Justice, she advised the Department’s leadership on various enforcement issues and oversaw certain antitrust, intellectual property rights enforcement, health care fraud, privacy, and telecommunications matters. As a prosecutor in the US Attorney’s Offices for the Eastern District of Virginia and the District of Maryland, she investigated and prosecuted cases involving narcotics trafficking, health care and immigration fraud, money laundering, export control violations, and child sex trafficking, winning every trial and appeal.

Marisa serves on the Boards of Directors of the Public Policy Institute of California and the Bar Association of San Francisco’s Justice & Diversity Center, and teaches trial advocacy at Stanford Law School as a guest instructor. She is a former President of the Korean American Bar Association of Northern California. Marisa’s pro bono work has included the representation of indigent tenants facing eviction, as well as the representation of bar associations in the United States and California Supreme Courts, in support of individuals whose constitutional rights have been violated.

Marisa served as Developments Editor of the Harvard Law Review and as a law clerk to the Honorable Robert Boochever of the U.S. Court of Appeals for the Ninth Circuit.

Representative Litigation Matters

  • Represented technology company in high-stakes litigation regarding alleged breaches of a strategic agreement involving well-known browser and search engine.
  • Representing environmental and radiological services provider, officers, and directors in environmental enforcement action brought by California Attorney General’s Office
  • Represented wealth management company and executive in high-stakes employee mobility case; after winning preliminary injunction, case settled on favorable terms.
  • Represented a Software-as-a-Service (SaaS) company in a bet-the-company arbitration involving misappropriation of the client’s intellectual property, and the systematic poaching of its customers, which resulted in a significant settlement.
  • Represented international robotics company in high-stakes, commercial dispute involving automotive and automation technology.
  • Trial counsel for a technology company in a three-week trade secret misappropriation, breach of contract, patent inventorship, and trademark case in which the jury returned a complete defense verdict on all eight trade secret claims, contract claims, and patent claim; awarded nominal damages of $1 each on the trademark claims.
  • Represented financial services institution in a case involving trade secret theft, unfair competition, conversion, and other tort claims arising out of movement of plaintiff’s employees to client.
  • Represented clients in privacy and Electronics Communications Privacy Act (ECPA) litigation involving allegations of video camera spying in a property rented via a global online platform; following our filing of a motion to dismiss, case settled.
  • Represented a major health care group purchasing organization in a complex product liability case; prevailed on a motion to dismiss and thereafter secured the swift dismissal of client.
  • Trial and appellate counsel for officers and directors of a major utility in high-profile shareholder derivative actions.
  • Trial counsel in patent infringement action on behalf of a technology and cybersecurity company in a nearly four-week trial involving link load balancing patents; won multi-million-dollar jury verdict in favor of client.
  • Defeated national and state consumer class actions alleging violations of the Sherman Act, Section 17200, and California Consumers Legal Remedies Act (CLRA); prevailed on dispositive motion and secured voluntary dismissal of a statewide unfair business practices action.
  • Represented employers and executives on employment matters, including defending statewide wage and hour class actions; won summary judgment in sexual harassment and constructive termination case; prevailed at trial; and resolved disputes favorably in mediation, including settlements with no or nominal monetary payments

Representative Appellate Matters

  • Representing aerospace company in the Fourth Circuit in an interlocutory appeal seeking to vacate an order issuing a preliminary injunction enjoining the sale of goods which allegedly bear infringing trademarks.
  • In a case of first impression, won the grant of a rare petition for writ of mandate for an iconic theme park and entertainment company in the California Court of Appeal, Second Appellate District, thereby vacating an order of the Superior Court denying the client’s motion to transfer venue.
  • Secured, on behalf of a well-known technology company, the summary dismissal of a petition for writ of mandate in the California Court of Appeal, Sixth Appellate District, thereby preserving a favorable trial court order regarding attorney-client privileged documents.
  • Represented the American Bar Association as amicus curiae in the U.S. Supreme Court in Lee v. United States, 137 S.Ct. 1958, 2017 WL 2694701 (2017), in support of an Asian-American immigrant; the Court held, 6-2, that a non-citizen defendant who pleads guilty based upon erroneous legal advice about the deportation consequences of a plea can establish Strickland prejudice under the Sixth Amendment.
  • Representing the Bar Association of San Francisco, the Los Angeles County Bar Association, and the Santa Clara County Bar Association in landmark constitutional challenge to California’s money bail system in the California Supreme Court in In re Humphrey, No. S247278
  • Represented the Bar Association of San Francisco and the Los Angeles County Bar Association as amici curiae in the California Supreme Court in Heller Ehrman LLP v. Davis Wright Tremaine LLP, 4 Cal. 5th 467 (2018), in support of four law firms; the Court sustained the position urged by our clients that a dissolved law firm has no property interest in legal matters handled on an hourly basis.

Representative Enforcement and Investigation Matters

  • Represented iconic U.S. technology company with respect to internal investigation of allegations of gray market diversion of products in Latin America
  • Represented US global engineering company with respect to multiple Foreign Corrupt Practices Act (FCPA) matters, including FCPA and anti-corruption due diligence in connection with a $250 million construction project in Asia
  • Represented board member of foreign automotive company and executive in FBI investigation of potential money laundering and other crimes; no action taken against client
  • Representing CEO of health care provider in a civil and criminal federal and California False Claims Act investigation of alleged health care fraud by the United States Attorney’s Office and the California Attorney General’s Office
  • Represented clients in a civil and criminal False Claims Act investigation of alleged health care fraud by the United States Attorney’s Office, DOJ’s Civil Fraud Section and the US Department of Health and Human Services (HHS) Office of Inspector General
  • Represented hospital in connection with civil and criminal False Claims Act investigation of alleged health care fraud
  • Represented a major managed care organization in a State Attorney General investigation of alleged antitrust violations with respect to market for specialized medical services; no action taken against client
  • Represented a prominent biotechnology company in an internal investigation of potential Anti-Kickback Statute violations
  • Advised major Asian energy company with respect to federal antitrust criminal matters
  • Represented high-profile, venture capital-backed health care technology company with respect to internal investigation of #MeToo sexual assault allegations involving company leadership and corporate governance issues
  • Represented non-profit corporation in investigation and favorable pre-litigation mediation and resolution of highly-charged sexual assault allegations leveled by co-executive director against a Board member and co-executive director
  • Represented a sports and leisure product company in a California Attorney General inquiry regarding alleged false advertising on a leading social networking website; no action taken against client
  • Represented an international cosmetics and skin care company in a State Attorney General investigation of alleged false advertising on client’s website; no action taken against client


Admitted to practice: California, District of Columbia, U.S. Supreme Court, U.S. Court of Appeals for the Ninth Circuit, U.S. Court of Appeals for the Fourth Circuit, U.S. Court of Appeals for the Federal Circuit, U.S. District Court for the Northern District of California, U.S. District Court for the Central District of California, and U.S. District Court for the Southern District of Texas.

Speeches & Presentations

Client Alerts & Newsletters

Media Mentions

Firm News & Announcements

Mar.24.2020 Crowell & Moring Files Amici Curiae Brief on Behalf of Leading Former U.S. Diplomatic and Government Officials in Climate Change Case Upholding California Cap and Trade Memorandum with Quebec
Jan.22.2020 Crowell & Moring Files U.S. Supreme Court Brief on Behalf of the American Bar Association Calling for Review of When the Wrongfully Convicted Can Seek Damages
Nov.05.2019 Global Investigations Review Names Crowell & Moring’s White Collar & Regulatory Enforcement Group to “GIR 100” Fifth Year in a Row
Sep.20.2019 Super Lawyers Recognizes 82 Crowell & Moring Lawyers Across United States
Apr.11.2019 Experienced Trial Lawyer A. Marisa Chun Joins Crowell & Moring’s San Francisco Office