Brian Klein
An accomplished and renowned trial attorney, Brian Klein is known for fierce and successful advocacy for clients in a wide variety of federal and state forums across the country. He is a former federal prosecutor who handles high-stakes civil litigation and criminal and regulatory defense matters, including those involving the DOJ, SEC, CFTC, FTC, CFPB, and state authorities.
Brian’s clients are successful entrepreneurs and professionals, fast growing and innovative companies, and larger companies, who are often in the technology and finance industries. Based on his accomplishments, Brian has been recognized as one of the nation’s top five financial technology attorneys, one of the top 100 attorneys in California, and Chambers has noted that he is “known as the guy you call when you get in trouble.”
As a leading litigator for those in technology and finance, Brian speaks internationally about cutting-edge litigation issues involving cyber security, data privacy, NFTs, and cryptocurrency. He also chairs the American Bar Association’s annual blockchain and cryptocurrency national institute. And for years he has taught a federal criminal practice seminar at the USC Gould School of Law, and he has guest lectured on legal issues at, among others, Yale Law School (white collar criminal defense) and the University of Michigan (cybersecurity).
Brian is admitted to practice in the states of California, Washington, and New York and before numerous federal courts around the country, including the Central and Northern Districts of California, the Western District of Washington, and the Southern and Eastern Districts of New York, as well as the U.S. Supreme Court.
He graduated from New York University School of Law and received his undergraduate degree from the University of Washington.
Representative Matters
- Representing Frances Haugen, the “Facebook Whistleblower,” including appearing with her when she testified before the U.S. Senate.
- Defended the alleged Capitol One hacker Paige Thompson (which involved one of the largest purported data breaches in history), obtaining acquittals at trial for her on the counts requiring prison time and a no prison time sentence in the face of the Seattle federal prosecutors asking for a seven-year prison sentence.
- Secured a declination to prosecute for a construction company CEO in a public corruption investigation conducted by federal prosecutors in Los Angeles.
- Defended Arthur and Kathleen Breitman, as well as their company, in connection with securities class action lawsuits in San Francisco involving the Tezos crowdfunding, which raised over $230 million.
- Represented Block.one in connection with its settlement with the SEC in which it paid a $24 million penalty in connection with its $4 billion token sale.
- Defended Marcus Hutchins, who is known worldwide for stopping the “WannaCry” ransomware attack in May 2017, in a federal prosecution out of Milwaukee for cybercrimes from his youth. Marcus pleaded guilty, was sentenced to no prison time, and without precedent, the district court encouraged him to seek a pardon.
- Represented Kraken in connection with its settlement with the SEC regarding its staking program.
- Defended a digital currency trader in federal court in Colorado against an unlicensed money transmitter criminal charge, securing dismissal of the case before trial.
- Obtained a complete acquittal at a jury trial in New York City for a boxer charged with assault with a deadly weapon in state court.
- Secured a no action letter from the SEC in connection with a years long investigation of a major digital token offering.
- Successfully handled the defense of Cesar Millan (the “Dog Whisperer”) when the Los Angeles County Department of Animal Control and District Attorney’s Office investigated allegations of animal abuse tied to one of Mr. Millan’s television shows. The authorities ultimately concluded Mr. Millan did nothing wrong and did not bring any charges.
- Obtained a declination to bring charges for a client from federal prosecutors in San Diego in a money laundering-related case.
- Represented Erik Voorhees, a prominent early Bitcoin adopter, in his settlement with the SEC in an investigation.
- Secured from the Los Angeles County District Attorney’s Office a declination to charge a high-profile client accused of sexual assault by someone the client met on a dating app.
- Represented a film production company in a Los Angeles-based federal action to enforce trademark rights that resulted in a settlement favorable to the client.
- Defended a digital currency company in a state securities division investigation based out of the Midwest (no enforcement action was brought).
- Represented a U.S.-based technology company in a contract dispute with an Australian entertainment company that resulted in a settlement favorable to the client.
- Successfully defended a hazardous waste cleanup company facing multiple California state criminal charges, securing dismissal of all charges before trial.
Professional Associations and Memberships
- American Bar Association
- National Association of Criminal Defense Attorneys
- Los Angeles County Bar Association
- Benchmark Litigation Star 2024
- Super Lawyer 2024
Newsroom
- Four Waymaker Partners Honored as Benchmark Litigation Stars 2025
- Brian Klein and Teresa Huggins Achieve Significant Victory with New York Judge’s Ruling on Defunct Cryptocurrency Exchange Bitfloor
- Granting Waymaker Motion, Florida Court Dismisses Complaint Against Cryptocurrency Exchange Payward, Inc.
- Brian Klein Quoted by Law360 about U.S. Senator Robert Menendez Guilty Verdict
- Brian Klein and Keri Axel Argue Issues of First Impression in Criminal Prosecution of Tornado Cash Co-Developer Roman Storm
- Chambers USA 2024 Ranks Waymaker for Litigation: General Commercial: Highly Regarded - California
- Brian Klein Quoted by Reuters about Archegos Founder Bill Hwang’s Trial
- Brian Klein Quoted by Law360 in Story about Cases to Watch in 2024
- Five Partners Named Southern California Super Lawyers 2024
- Waymaker, Brian Klein and Ashley Martabano Earn Chambers 2024 FinTech Ranking
- Partner Brian Klein Speaks to Bloomberg about Sam Bankman-Fried Testifying at His Criminal Trial
- Four Waymaker Partners Recognized as Benchmark Litigation Stars 2024
- Bloomberg Law Podcast Interviews Brian Klein about Sam Bankman-Fried’s Criminal Trial
- Brian Klein Quoted by Wall Street Journal in Story about Trump’s Multiple Trials
- Partner Brian Klein to Speak on Trends In Cyber Enforcement at SoCal’s ABA White Collar Crime Committee, February 21, 2023
- Wall Street Journal Reports on Alleged Crypto Market Manipulation Scheme by Partner Brian Klein’s Client
- Partner Brian Klein Quoted About Notorious Gambler Suing Casinos From Prison
- Partner Brian Klein Named One of Daily Journal’s Top White Collar Attorneys 2022
- Waymaker LLP and Partner Brian Klein Earn Chambers 2023 FinTech Ranking
- Partner Brian Klein Speaks About Key Enforcement Actions at the ABA’s Blockchain and Cryptocurrency National Institute
- Brian Klein Quoted by the Wall Street Journal on Winning Probation for the Firm’s Client, the Alleged Capital One Hacker, Paige Thompson
- Four Partners and Waymaker Recognized in Benchmark Litigation California 2023
- Partner Brian Klein Named one of California’s Top 100 Lawyers by the Daily Journal
- Partner Brian Klein Named Fintech/Blockchain/Crypto Trailblazer 2022 by the National Law Journal
- Partner Brian Klein Quoted By Law360 about Cybersecurity Bill Authored by Sens. Lummis and Gillibrand
- Partners Keri Curtis Axel, Ryan Baker and Brian Klein Named Elite Boutique Trailblazers 2022 by the National Law Journal
- The Trial of Paige Thompson, the Alleged Capital One Hacker, is Underway with Brian Klein, Melissa Meister, and Emily Stierwalt Acting as Defense Counsel
- Partner Brian Klein Quoted By Law360 about the Ninth Circuit’s Recent Landmark Cybercrime Decision and Firm Client Paige Thompson
- Partners Teresa Huggins and Brian Klein Speak at 2022 TechGC’s Invitation Only Fullstack Conference