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Marc A. Wallenstein

Marc Wallenstein
312 641 9750
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800 678 9529
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Marc A. Wallenstein is a partner at the firm.  He is a former federal prosecutor and has more than a decade of experience in federal public service.  Marc has tried numerous cases to verdict and appeared in court on a daily or weekly basis for much of his career.

Marc is currently on the lead or co-lead class counsel teams in four class action lawsuits against Google. Marc recently served as trial counsel for thousands of minor league baseball players seeking to be paid minimum wage by Major League Baseball. The lawsuit settled on the eve of trial for $185 million, which represented 137% of the unpaid wages owed to class members, as well as significant injunctive relief that will vindicate the rights of current and future minor league players for years to come.

Marc is a graduate of Harvard College and Yale Law School.  After law school, he served as a law clerk in the Southern District of New York and on the United States Court of Appeals for the Ninth Circuit.

Before joining Korein Tillery, Marc served for six years as an Assistant U.S. Attorney in the District of Hawaii, where he gained expertise in national security matters, financial crime, procurement fraud, health care fraud, public corruption, cyber crime, environmental crime, and crimes against children.  Marc served as Computer Hacking and Intellectual Property (CHIP) Coordinator, responsible for complex issues related to computer crime and electronically stored information, as an Anti-Terrorism Advisory Coordinator (ATAC), responsible for national security investigations and prosecutions, and as a member of the Department of Justice’s Cryptocurrency Working Group.  Marc successfully prosecuted the first terrorism case ever brought against an active duty member of the U.S. military, and obtained record fines in numerous environmental cases, including the largest marine pollution fine in District history.  Marc has received several awards from the Department of Justice and the Federal Bureau of Investigation for his work.

Prior to his time at the Department of Justice, Marc served for three years as a Prosecutor at the Office of the Chief Prosecutor of Military Commissions, U.S. Department of Defense.  In that capacity, Marc prosecuted violations of the law of war committed by enemy alien belligerents before a military commission in Guantanamo Bay, Cuba.  Among other responsibilities, Marc served as a litigation team chief, managing attorneys, paralegals, FBI agents, analysts, and staff.  Marc also served as an appellate and pretrial motions attorney on a range of cases, including the prosecution of Khalid Shaikh Mohammed and four others accused of perpetrating the attacks of September 11, 2001.

Marc previously conducted complex civil litigation in Washington DC.  Among other matters, he represented the National Credit Union Administration against Wall Street banks for failed investments in residential mortgage-backed securities, with co-counsel from Korein Tillery.

Marc maintained an active Top Secret/SCI security clearance throughout his federal employment.

Marc is admitted to practice law in New York, Washington DC, Texas, Hawaii, Connecticut, and numerous federal district and circuit courts around the country.

Before he became an attorney, Marc worked as a travel writer in Italy, Australia, and Hawaii.  Marc works from his home in New Haven, Connecticut. 

Representative Matters at Korein Tillery
  • In Csupo v. Google and Taylor v. Google, Marc is seeking redress for Google’s unlawful consumption of cellular data on behalf of Android users in California and nationwide.  Marc is among the lead lawyers managing both lawsuits.
  • In Genius v. Google, Marc is pursuing antitrust claims against Google on behalf of a class of publishers of online advertisements, alleging that Google has rigged the online ad auction market, generating billions of dollars of unlawful profit for itself, while making online advertisement more expensive for newspapers, independent journalists, and all the many other websites that rely on advertising revenue to survive.
  • In Carr v. Google, Marc is challenging Google’s anti-competitive conduct in the Google Play Store on behalf of a class of consumers nationwide, including the 30% fee that Google charges for all in-app purchases.
  • In Senne v. Major League Baseball, Marc successfully pursued Fair Labor Standards Act and similar state law claims against Major League Baseball and major league clubs, for unlawfully failing to pay minor league players wages during spring training, among other claims, resulting in a $185 million settlement.
Education
  • Yale Law School

    • J.D. - 2006​

    • Senior Editor, Yale Law and Policy Review

  • Harvard College

    • A.B., Philosophy, cum laude, 2002

    • John Harvard Scholarship

Prior Legal Experience
  • Assistant U.S. Attorney, U.S. Attorney’s Office, District of Hawaii, U.S. Department of Justice (2015-2021)

  • Prosecutor, Office of the Chief Prosecutor of Military Commissions, U.S. Department of Defense (2012-2015)

  • Law Clerk to Hon. Richard R. Clifton, United States Court of Appeals for the Ninth Circuit (2007-2008)

  • Adjunct Professor, University of Hawaii Richardson School of Law (2008)

  • Law Clerk to Hon. Barbara S. Jones, United States District Court for the Southern District of New York (2006-2007)

Representative Matters and Responsibilities at the Department of Justice
  • Managed yearlong undercover FBI operation that culminated in the first prosecution of an active duty member of the U.S. military for providing material support to a foreign terrorist organization, which was also the first terrorism prosecution ever brought in Hawaii.  The defendant, a Sergeant First Class in the U.S. Army, was convicted of providing material support to ISIS, and received the longest Rule 11(c)(1)(C) sentence in a material support case to date.   Presented as a case study to other national security prosecutors and agents at the Department of Justice’s National Advocacy Center. 

  • Negotiated largest marine pollution (MARPOL) fine in the history of the District of Hawaii, against a multinational shipping conglomerate that unlawfully dumped oily bilge waste into the Pacific Ocean.  Implemented robust compliance plan.

  • Obtained largest criminal monetary penalty in a shark fin trafficking case in the United States, against a Japanese firm operating long-line fishing vessels on the high seas.

  • Successfully prosecuted a youth pastor who sexually exploited 15 young minors aged 7 to 13 years old.

  • Successfully conducted first federal trial for unlawful drone flight. 

  • Computer Hacking and Intellectual Property Coordinator, responsible for complex issues related to computer crime and electronically stored information. 

  • Anti-Terrorism Advisory Coordinator, responsible for national security investigations and prosecutions. 

  • Member of Department of Justice’s Cryptocurrency Working Group. 

  • Supervised a team of active duty military Special Assistant U.S. Attorneys.

  • Outer-Island Coordinator, managing cases arising in Volcano, Haleakalā, and Kalaupapa National Parks. 

  • Treasurer of the National Association of Assistant U.S. Attorneys, representing the interests of the more than 5,500 federal prosecutors nationwide. 

Representative Matters at the Department of Defense
  • Conducted complex pretrial and appellate litigation in the prosecutions of:

    • ​Khalid Shaikh Mohammed and four others accused of perpetrating the attacks of September 11, 2001;

    • Hambali, the alleged mastermind of the 2002 bombings in Bali, Indonesia;

    • Abd al Hadi al Iraqi, alleged commander of all al Qaeda forces in Afghanistan and Pakistan from 2001 to 2004;

    • Abd al Rahim al Nashiri, the alleged mastermind of the bombing of the U.S.S. Cole.

    • Ali Hamza Ahmad Suliman al Bahlul

Representative Matters in Prior Private Practice
  • Served as relator’s counsel in a non-intervened qui tam litigation against the world’s largest biotechnology company, which culminated in a $780 million global settlement just before trial.  Managed 14 attorneys and 11 staff reviewing six million pages of discovery.  Managed enforcement of 250+ subpoenas and notices.  Took 23 fact depositions and defended five expert depositions. 

  • Successfully represented the National Credit Union Administration against Wall Street banks for failed investments in residential mortgage-backed securities, which has led to recoveries of $5.2 billion.

  • Successfully represented the State of Tennessee in an original jurisdiction suit brought by the State of Mississippi before the United States Supreme Court, over $1 billion in groundwater rights to an interstate aquifer

  • Conducted confidential internal investigation of a multinational corporation.  Interviewed numerous fact witnesses.  Managed document review team of nearly 30 attorneys.

Awards
  • James Peabody Gardner Memorial Traveling Fellowship (2002-2003)

  • National Champion, Lincoln Douglas Debate (1997)

  • Eagle Scout (1995)

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