MARK GUERRERA, co-leader of the Commercial Litigation and Disputes group, represents corporations in commercial litigation, dispute resolution, and in government investigations. He has tried cases in federal court and before regulatory agencies, and has defended clients in cross-border litigation in Italy, Liechtenstein, Switzerland, and the Cayman Islands, among others. Mark has represented clients in the financial services, government contracting, real estate, pharmaceutical, energy, and telecommunications industries in litigation involving allegations of fraud and other business torts, breach of fiduciary duty, deepening insolvency, market manipulation, unfair business practices, securities fraud, breach of contract and violations of state and federal statutes, including the False Claims Act and RICO. He also has litigated class action securities matters, government contracts disputes, bid protests and intellectual property disputes. A number of the cases Mark has litigated have involved multi-billion dollar damage claims.
Mark also has conducted internal investigations on behalf of companies in the U.S. and abroad has defended companies in connection with government investigations regarding allegations of fraud, accounting irregularities, employee misconduct and violations of the False Claims Act, anti-bribery, anti-money laundering, federal securities and banking laws.
Recent representations include:
- Advising clients on contractual and related issues arising from the COVID-19 pandemic.
- Representation of a telecommunications company in federal court actions alleging violations of the Telecommunications Act, obtaining multiple victories on summary judgment.
- Representation of a commercial real estate company in litigation regarding property rights and alleging claims for breach of contract.
- Representation of Big Four accounting firm partner and employee in PCAOB investigation.
- Representation of pharmaceutical manufacturers in connection with affirmative claims for violations of the Lanham Act.
- Representation of pharmaceutical distributor in federal court litigation, alleging claims of fraud and breach of contract.
- Representation of pharmaceutical manufacturer in connection with disputes regarding the Prescription Drug User Fee Act.
- Representation of a foreign executive in connection with a multinational bribery investigation and related proceedings in the United States, Europe and Africa.
- Representation of a GSA Schedule contractor in connection with a qui tam lawsuit and related DOJ investigation under the False Claims Act alleging violations of the price reduction clause.
- Representation of an interstate natural gas pipeline in an enforcement proceeding before the Federal Energy Regulatory Commission.
- Representation of pharmaceutical manufacturers in connection with internal reviews of FDA regulatory issues.
- Representation of a major financial institution in a series of cases in the United States and abroad arising out of the collapse of Italian dairy giant, Parmalat S.p.A. Obtained multiple victories on motions to dismiss, summary judgment, and at trial — all of which were affirmed. In re Parmalat, 497 F. Supp. 2d 526 (S.D.N.Y. 2007); In re Parmalat, 570 F. Supp. 2d 521 (S.D.N.Y. 2008); Smith v. BoA, 501 F. Supp. 2d 560 (S.D.N.Y. 2007), PCFL v. BoA, 659 F. Supp. 2d 504 (S.D.N.Y. 2009); FHL v. BoA, 684 F. Supp. 2d 453 (S.D.N.Y. 2010); Pappas v. BoA, 309 Fed. Appx. 536 (2d Cir. 2009); PCFL v. BoA, 412 Fed. Appx. 325 (2d Cir. 2011); FHL v. BoA, 423 Fed. Appx. 73 (2d Cir. 2011).
- Representation of a financial service provider in connection with anti-money laundering compliance matters and related government investigations.
- Representation of defense contractor in a four week trial against the United States Air Force.
- Representation of a satellite manufacturer in a six week international arbitration, successfully defeating all claims asserted by counterparty.
- Advised government contractors regarding the negotiation of federal prime contracts and subcontracts.
- Advised clients regarding compliance with the Buy American Act and Trade Agreements Act;
- Representation of a major financial institution in qui tam “whistleblower” lawsuits under the False Claims Act regarding securitization and foreclosure practices. See, e.g., U.S. ex rel. Adams v. Wells Fargo Bank, N.A., 2013 U.S. Dist. LEXIS 175322 (D. Nev. Dec. 11, 2013).
- Representation of a nursing home owner in a DOJ investigation under the False Claims Act.
Prior to joining Sidley, Mark clerked at the Armed Services Board of Contract Appeals.