William Sullivan is senior counsel of Paul Hastings Litigation Department and is based in the firm's Los Angeles office. Mr. Sullivan has substantial experience in complex business litigation, including the representation of public companies in the defense of federal and state securities class actions, derivative actions and regulatory proceedings. Most of these cases involve claims arising out of public offerings, mergers and acquisitions, disclosure obligations, insider trading, accounting practices or allegations of breaches of fiduciary duties. Mr. Sullivan argued and won the ground-breaking Dura Pharmaceuticals case before the United States Supreme Court which established the standard for loss causation in federal securities class actions. Mr. Sullivan is a veteran trial lawyer who has tried cases involving stock valuations, fraud, forgery, license agreements, internet contract issues, whistle blower claims, employee termination, lender liability, fiduciary duties and breach of real estate contracts, among others. Mr. Sullivan has significant experience counseling public companies and frequently counsels boards of directors in special investigations. Mr. Sullivan also represents clients before the Securities and Exchange Commission. Mr. Sullivan has substantial appellate experience, including before the United States Supreme Court.
Previously, Mr. Sullivan served as the Global Chair of the Litigation Department, Chair of the Los Angeles Litigation Department, and Chair of the firm's Securities Litigation practice.
- Honored as "California Lawyer of the Year" in Securities Law
- Recognized as one of the Top 30 Securities Litigators in California and one of the Top 100 Most Influential Lawyers in California
- Honored as one of the Top 100 Lawyers in Los Angeles by The Los Angeles Business Journal
- Recognized as a leader in his field by Chambers USA
- Listed in The Best Lawyers in America and as a Legal Superstar in Securities Law 360
- University of California at Los Angeles School of Law, J.D., 1977
- University of California Berkeley, A.B., 1974 (with distinction)
- Dura Pharmaceuticals, Inc. Securities Litigation: Mr. Sullivan argued this landmark case before the United States Supreme Court. This argument was noted as the most important securities litigation case argued before the Supreme Court in a decade. The unanimous decision in favor of Mr. Sullivan’s client is now the controlling case on loss causation. From the onset of the litigation, we represented Dura and its officers and directors in this consolidated federal court securities class action filed in the Southern District of California.
- In re UBS Auction Rate Securities Litigation: We represented UBS in this high-profile series of cases involving auction rate securities arising out of the global credit crisis. These main cases are pending in the United States District Court for the Southern District of New York. Through a series of motions, we were able to defeat every claim and theory of liability that plaintiffs tried to allege against our clients. First, we obtained a defense judgment against claims brought under the Investment Advisers Act of 1940 and under New York state law. Next, we won a motion to dismiss claims brought under the Securities Exchange Act of 1934 based on our argument that the named plaintiffs could not establish compensable damages in the case -- a decision which was later followed in several other cases involving auction rate securities. Finally, when a new set of plaintiffs filed a new complaint based on yet another theory, the court again granted our motion to dismiss, agreeing with us that the plaintiffs' allegations could not support a claim for market manipulation. We also counsel UBS on numerous other related cases and arbitrations filed around the country, including one of the cases resulted in a dismissal of all claims and is reported at Kassover v. UBS AG, 619 F.Supp.2d 28 (S.D.N.Y. Dec 19, 2008). Our team obtained a key industry leading result for UBS. We had the first decision dismissing an ARS case and all the other investment banks used our motion as a model.
- Jacobs Engineering: We represented the directors of Jacobs Engineering Group Inc., as well as the company’s executive compensation consultant, Frederic W. Cook & Co., Inc., in a shareholder derivative action. The shareholders claimed that the directors violated their fiduciary duties owed to Jacobs regarding the directors’ approval of the company’s executive compensation. The shareholders also claimed that Frederic W. Cook aided and abetted the alleged breach of fiduciary duty and breached its contract with Jacobs regarding its advice on Jacobs’ executive compensation. After hearing argument on the directors’ motion to dismiss, the Los Angeles Superior Court issued an order dismissing all claims and entered final judgment in favor of the defendants.
- Morgan Stanley: We are representing Morgan Stanley, one of its officers, and several of its investment funds in a breach of fiduciary duty and fraud case brought in Honolulu, Hawaii by more than 50 plaintiffs, including the former governor of Hawaii, arising out of Morgan Stanley's investment in and subsequent sale of Pihana, Inc. Plaintiffs alleged damages against more than thirty total defendants in excess of US$500 million. The case has been pending for approximately two years and raised numerous issues of first legal impression, including the question of whether the internal affairs doctrine required application of Delaware law on the statute of limitations to the case brought in Hawaii. We successfully obtained dismissal of the case on limitations and other grounds and obtained an award of $1 million in attorneys' fees. We thereafter settled the case on favorable terms during an appeal to the Hawaii Supreme Court, and then defended the settlement against challenges by co-defendants in the trial court.
- Boulder: United States District Court for the District of Colorado: We obtained dismissal on a motion to dismiss in favor of a mutual fund client and its independent directors of purported nationwide class action brought under the Investment Company Act of 1940 which sought to enjoin a rights offering to shareholders.
- Countrywide: We represent several former senior executives of Countrywide Financial Corporation in numerous securities cases brought by plaintiffs across the country which had allegedly purchased, collectively, over a billion dollars worth of mortgage-backed securities issued by the company. In these matters, our clients, who had signed "shelf" registration statements underlying the mortgage-backed securities, faced claims for, inter alia, alleged violations of the federal securities laws, the Blue Sky laws of several states, and various common law claims. Through our creative and aggressive motion practice, our clients were dismissed entirely from eight district court cases and one 9th Circuit appeal case.
- Emergent: Paul Hastings represented Emergent Group, Inc. and its former board members in three consolidated class action complaints filed in Los Angeles Superior Court on and after February 22, 2011. The lawsuits were filed in connection with the tender offer sale of Emergent to Universal Hospital Services, Inc. ("UHS"). The complaints each alleged that the individual defendants breached fiduciary duties owed to Emergent’s public shareholders by agreeing to a sale for an unfair price, with improper preclusive deal protection devices , and through a process that failed to maximize the value of Emergent to its public shareholders. The complaints sought, among other things, declaratory and injunctive relief including to prohibit the Defendants from consummating the transaction and other forms of equitable relief.
- Universal: Paul Hastings represents Universal Entertainment Corporation ("Universal"), its wholly owned subsidiary, Aruze USA, Inc. ("Aruze USA"), and its Chairman and President, Kazuo Okada, in litigation involving a purported stock redemption by Wynn Resorts, Inc. ("Wynn Resorts") of Aruze USA’s $2.9 billion equity investment in Wynn Resorts. Immediately following the purported redemption, Wynn Resorts filed a complaint against Mr. Okada, Universal, and Aruze USA for declaratory relief and breach of fiduciary duty. On March 12, 2012, Universal and Aruze USA filed a counterclaim asserting, among other claims, violations of the Federal Securities Act of 1934 under the "forced seller" doctrine, related to the purported redemption, which would produce a massive, illegal windfall for Wynn Resorts.
- Paul Hastings Ranked as Top Three Firm for New Rankings and Recognized for Numerous Practice Strength and Growth in Chambers USA 2021 - May 21st, 2021
- Paul Hastings Named to World’s Top 10 Best Investigations Practices by Global Investigations Review - October 23rd, 2020
- Benchmark Litigation Distinguishes Paul Hastings’ IP Practice with Top-Tier National Ranking - October 14th, 2020
- Paul Hastings Practices and Lawyers Score Top Rankings in Chambers USA 2020 - May 1st, 2020
- Paul Hastings Practices and Lawyers Score Top Rankings in Chambers USA 2019 - May 1st, 2019
- Paul Hastings Practices and Lawyers Score Top Rankings in Chambers USA 2018 - May 11th, 2018
- Paul Hastings Practices and Lawyers Score Top Rankings in Chambers USA 2017 - June 5th, 2017
- Paul Hastings’ Litigators Score High Rankings in 2017 Benchmark Litigation - October 21st, 2016
- Paul Hastings Practices and Lawyers Score Top Rankings in Chambers USA 2016 - June 8th, 2016
- Paul Hastings Practices and Lawyers Score Top Rankings in Chambers USA 2015 - May 20th, 2015
- Paul Hastings Practices and Lawyers Score Top Rankings in Chambers USA 2014 - May 27th, 2014
- Paul Hastings Extensive Practice Strength Highlighted in The Legal 500 United States 2013 - June 5th, 2013
- Paul Hastings Employment Practice Honored with Chambers ''Award for Excellence'' and Firms Leading Practices and Lawyers Ranked in Chambers USA 2013 - May 27th, 2013
- Paul Hastings Further Strengthens Global Compliance & Disputes and Global Banking & Payment Systems Practice Groups with Addition of New Partner - October 15th, 2012
- Paul Hastings Excels in Chambers USA 2012 Guide - June 7th, 2012
- Paul Hastings Continues Antitrust and Competition Expansion with Former Department of Justice Executive in DC - June 1st, 2012
- Paul Hastings Secures Dismissal of Say-on-pay Shareholder Derivative Action - March 14th, 2012
- Paul Hastings Excels in Chambers USA 2011 Guide - June 10th, 2011
- Paul Hastings Soars in 2011 Edition of Legal 500 US - June 1st, 2011
- Best Lawyers Names 91 Lawyers to 2011 Edition of Rankings - August 16th, 2010
- Paul Hastings Litigation Practice Recognized by Chambers USA 2021 - May 28th, 2021
- Recognized by Chambers USA 2021 - May 21st, 2021
- Recognized by Chambers USA 2020 - May 1st, 2020
- Ranked by Chambers USA 2019 - April 26th, 2019
- Recognized by Chambers USA 2018 - May 15th, 2018
- Recognized by Chambers USA 2017 - June 5th, 2017
- Benchmark Litigation 2017 - October 21st, 2016
- Recognized by Chambers USA 2016 - June 8th, 2016
- Benchmark Litigation 2016 - December 9th, 2015
- Daily Journal “Top 100 Lawyers in California” - September 10th, 2014
- Recognized by the The Daily Journal among the Top 100 Leading Lawyers - September 22nd, 2010
- Recognized by Chambers USA 2008 - June 13th, 2008
- COVID-19 Paul Hastings LLP Hospitality & Leisure Client Alert - March 16th, 2020
- Lowering the Bar on Tender Offer Claims: The Ninth Circuit Adopts a Negligence Pleading Standard - May 1st, 2018
- Supreme Court Rules That Securities Act Claims Can Be Brought in State Court - April 2nd, 2018
- The U.S. Supreme Court Decides American Pipe Tolling Does Not Apply to Statutes of Repose - June 28th, 2017
- Extending Omnicare Beyond The Section 11 Case - May 25th, 2017
- Omnicare Extended: The Ninth Circuit Adopts a Heightened Falsity Pleading Standard for Section 10(b) and Rule 10b-5 Material Misstatement Claims - May 16th, 2017
- The U.S. Supreme Court Hears Oral Argument on Whether American Pipe Tolling Applies to Statutes of Repose - May 11th, 2017
- Blowing the Whistle: Ninth Circuit Rejects Narrow Interpretation of Dodd-Frank’s “Whistleblower” Protections - March 10th, 2017
- Decoding The Import Of A Company’s Code Of Ethics - February 6th, 2017
- Decoding the Import of a Company’s Code of Ethics in a Securities Class Action: The Ninth Circuit Adopts an Objective Approach to Determining Whether Statements Regarding a Company’s Code of Ethics May Become Material Misrepresentations - February 2nd, 2017
- Ninth Circuit Affirms: SLUSA Does Not Provide Independent Basis for Federal Question Jurisdiction - January 4th, 2017
- Private Fund Report—Summary of Key Developments—Winter 2016 - January 3rd, 2017
- Gift Giving and Insider Trading: The Supreme Court Rules in Government’s Favor in Significant Insider Trading Case - December 7th, 2016
- Private Fund Report—Summary of Key Developments—Spring 2016 - July 14th, 2016
- Recent SEC Enforcement Action Merits a Second Look by Private Equity Firms and Fundless Sponsors at Broker-Dealer Registration - June 20th, 2016
- Hedge Fund Report: Summary of Key Developments - Fall 2015 - December 21st, 2015
- Ninth Circuit Clarifies Application of 'Adverse Interest Exception' in Securities Class Actions - November 3rd, 2015
- The Yates Memorandum: Increasing the Perils of Parallel Proceedings - October 28th, 2015
- Regulatory Update: Recent Judicial Decisions Bring Changes to Financial Services Industry - June 2nd, 2015
- Hedge Fund Report - Summary of Key Developments - Spring 2015 - June 1st, 2015
Engagement & Publications
- Frequent panelist and speaker on litigation matters