Alison L. Plessman

Ms. Plessman is a co-founder of Hueston Hennigan LLP. She represents plaintiffs and defendants in a wide range of high-stakes litigation matters involving securities, healthcare, and insurance fraud, trade secret misappropriation, RICO violations, accounting irregularities and market manipulation, professional negligence, and breaches of contract and fiduciary duties. Ms. Plessman has also successfully defended companies, boards of directors, and individuals facing regulatory investigations and criminal enforcement actions, and she has obtained pre-indictment and post-indictment dismissals in numerous cases.

“This securities litigator wins big, particularly when her clients are the biggest on earth.”
-The Recorder, Lawyers on the Fast Track, June 24, 2013

In 2015 and 2017, Ms. Plessman was selected by the Daily Journal as one of the Top 100 Women Lawyers in California for her work on behalf of such varied clients as T-Mobile, Universal Music Group, and Pacific Select Fund, while simultaneously defending other notable clients facing regulatory or criminal exposure. In 2013, Ms. Plessman was selected by The Recorder as one of only 50 “California Lawyers on the Fast Track.” The list highlights attorneys in their first 10 years of practice who stand out among their peers based on career achievements and leadership roles within their practice, organization and community. Since 2016,  Ms. Plessman has been named a “Super Lawyer” by Super Lawyers Magazine, which in previous years had selected her as a “Rising Star.”

Ms. Plessman was previously a partner at Irell & Manella LLP. She began her legal career as an associate at Wachtell, Lipton, Rosen & Katz in New York City.

In addition to her practice, Ms. Plessman also serves on the Western Center on Law & Poverty Board of Directors, as well as on its finance and public relations committees. She also served on the Board of Governors of the Women Lawyers Association of Los Angeles (“WLALA”), serving as Co-Chair of WLALA’s Litigation Section from 2010 to 2012, and as Co-Chair of the Career Development and Life Balance Committee in 2012 and 2013.

“Plessman secured a $20 million order in favor of Pacific Select Fund in an investment mismanagement case.”
-The Recorder, Lawyers on the Fast Track, June 24, 2013

In June 2006, the Securities Litigation Report published her article, “Electronic Discovery and the Proposed Amendments to the Federal Rules of Civil Procedure.” The New York Law Journal published her article “Lessons from Moussaoui: The Ethics of Witness Prep,” in March 2006.

Representative Matters

  • Representing a leading global professional services company in an ongoing $800 million actuarial malpractice lawsuit.
  • Representing investment bank professional in ongoing U.S. Treasuries probe conducted by the Securities and Exchange Commission and the Commodity Futures Trading Commission.
  • Served as trial counsel for T-Mobile in a successful trade secrets lawsuit against the Chinese smartphone maker Huawei Technologies alleging the manufacturer stole T-Mobile’s smartphone testing robot.

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  • Successfully defended senior executive at a global investment firm in a multi-year investigation being conducted by the Securities and Exchange Commission, resulting in no charges or fines.
  • Successfully defended senior executive at international gaming company in whistleblower suit investigated by the Securities and Exchange Commission, resulting in no charges or fines.
  • Successfully defended Glaukos Corporation against a claim of inequitable conduct in a complex patent matter in Delaware federal court. The case settled three days before trial on favorable terms for our client.
  • Obtained dismissal of criminal mortgage fraud indictment after evidentiary hearings for prosecutorial misconduct; Dallas County District Attorney held in contempt (featured as “Hill Wins, Watkins Loses” in the Dallas Morning News) — Read the article.
  • Obtained $20 million for Pacific Life against Bank of New York Mellon at the summary judgment stage in a breach of contract and breach of fiduciary duty matter in investment mismanagement litigation, and later obtaining an additional $30 million for Pacific Life in a settlement on the eve of trial.
  • Represented Universal Music Group in a nine-figure negligence and breach of contract lawsuit concerning media assets that were destroyed in a fire at NBC Universal’s studio lot. Shortly before the start of trial, and after successfully adding a punitive damages claim, a favorable settlement was reached.
  • Served on the winning trial team in the $2.2 billion dollar insurance dispute between Silverstein Properties and several insurance companies concerning the collapse of the World Trade Center in the aftermath of the September 11 attacks.
  • Successfully Defended Kenneth Langone’s Invemed Associates in a disciplinary proceeding before the NASD (now FINRA) that resulted in what the New York Times called a ” withering,” “high-profile defeat” for the regulators.
  • Represented the New York Stock Exchange in litigation with dissident seatholders following the announcement of the NYSE’s historic merger with Archipelago. During the preliminary injunction hearing, the parties reached a settlement that allowed the vote on the merger to proceed as scheduled;
  • Successfully defended senior marketing executive at pharmaceutical company in off-label marketing criminal investigation, resulting in no charges or fines.
  • Represented an institutional health care provider in an internal investigation of alleged patient safety and standard of care violations and whistleblower retaliation.
  • Represented a consumer debt finance company in an internal investigation of alleged TCPA and FDCPA violations.
  • Resolved federal investigation of alleged celebrity privacy breaches at UCLA without charges or fines.
  • Defended an information technology services company in actions alleging negligence and breach of contract claims involving the computer security assessment of a credit card processor that was hacked and from which credit card information was stolen. The case settled favorably shortly after summary judgment briefing was filed.
  • Represented plaintiff environmental organizations in a series of successful challenges to the Navy’s use of environmentally harmful high-intensity sonar in training exercises, resulting in the issuance of court orders providing for injunctive relief against the Navy for its violation of U.S. environmental laws.
  • Obtained default judgment and settlement for a veteran who was defrauded out of his home through a loan modification scam – Article.
Alison Plessman

Alison L. Plessman

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Columbia Law School (J.D., 2003) Harlan Fiske Stone Scholar; Frederick H. Weisberg Award in Constitutional Law

University of Minnesota (B.A., Political Science, 1999) summa cum laude; Phi Beta Kappa; Phi Kappa Phi