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Joe Mamounas is a Litigation shareholder in Greenberg Traurig’s Miami office. With more than a decade of experience in trial practice, arbitration, and internal investigations and compliance, he has represented clients doing business in most industries, including private equity, financial and other services, telecommunications, and infrastructure.

Additionally, Joe represents plaintiffs and claimants in business-to-business disputes, breaches of representations and warranties and other M&A related claims, and international disputes, particularly with issues relating to Spain and Latin America. He also represents clients in international and domestic arbitrations, including before the American Arbitration Association (AAA), International Chamber of Commerce (ICC), International Centre for Dispute Resolution (ICDR), and Judicial Arbitration and Mediation Services (JAMS), in "post-deal," breaches of representations and warranties, and other confidential business matters involving up to hundreds of millions of dollars in damages.

Joe has handled complex corporate disputes in nationwide litigation, where he has prosecuted claims to verdict or other final award on behalf of business clients and defended against contract, corporate fraud, and other tort allegations in bet-the-company and other high-value cases. His experience also includes internal investigations and compliance matters involving asset forfeiture, Foreign Corrupt Practices Act (FCPA), import/export, and other criminal laws and regulations, including mission-critical circumstances parallel to threatened or pending civil litigation.

In every engagement, Joe is a relentless advocate for his clients, leveraging discovery and other investigative tools to achieve their strategic and business objectives.



  • ICC emergency arbitration as to international M&A transaction: For the seller of a multijurisdictional food-delivery platform, secured emergency injunctive relief preventing the purchaser from terminating the acquisition; the deal, valued at approximately $165 million, subsequently closed.
  • ICC arbitration on behalf of Latin American technology enterprise: Successfully prosecuted claims for specific performance and declaratory relief against a publicly traded German company.
  • Multijurisdictional mining dispute, including ICDR arbitration: Prosecuted post-deal claims by multibillion-dollar Russian manufacturer involving mining rights valued at more than $100 million in ICDR arbitration and related arbitrability and other court proceedings, resolving all client goals by settlement before the final merits hearing concluded.°
  • ICC arbitration on behalf of multibillion-dollar Spanish multinational: Represented a global Spanish conglomerate in an ICC arbitration pursuing claims, including for breach of representations and warranties and fraud, for more than $15 million; after a five-day liability hearing, the client's losses were fully resolved.°
  • AAA representations and warranties insurance arbitration: Acted on behalf of a global insurance provider in a dispute arising out of a representations and warranties policy and underlying breaches, in defense of alleged damages estimated at $10 million.°
  • ICC arbitration and related court action on behalf of U.S. aviation services company: Represented a U.S. aviation services company as to multimillion-dollar “post-M&A” claims against its former president and CEO.°
  • Streamlined JAMS private equity arbitration: Acted on behalf of a leading private equity firm, recovered nearly 50 percent of a portfolio company's purchase price for breached representations and warranties concerning the loss of a customer, plus legal fees after a four-day final hearing.°
  • ICC arbitration and related court case against senior manager: Represented a U.S. aviation services company in arbitration and related court case as to claims arising from the termination of a senior manager.°
  • JAMS aviation dispute and related litigation: Pursued breach of contract claims for a U.S. aviation services company, recovering much of the client's damages.°
  • ICDR hospitality arbitration: Brought claims for a Caribbean entity against a diversified multinational arising from the construction of an internationally acclaimed resort, resulting in an award satisfying the full amount of the client's claims after a three-day final hearing.°
  • ICDR arbitration: Acted on behalf of a prominent Dominican banking executive and negotiated a full resolution before final hearing.°
  • ICC electronics arbitration: Prosecuted claims by an Ecuadorian electronics distributor against a Korean electronics manufacturer for breach of distribution agreement.°
  • Internal investigation for prestigious private U.S. university: Led an internal investigation into potentially criminal allegations and related multimillion-dollar civil demands, which settled privately and pre-suit for less than 5 percent of the plaintiff's demand.°
  • Internal FCPA Investigation for Swiss global freight forwarder: Represented a global freight forwarder in on-the-ground internal interviews and document review relating to potential violations of the FCPA and other compliance issues.°
  • Investment funds in Rothstein Ponzi scheme: Successfully defended three investment funds against investors in Scott Rothstein's Ponzi scheme as to aiding and abetting, civil conspiracy and other claims, seeking to recover more than $43 million.°
  • Recovery of seized funds for Venezuelan financial services client: Secured the return of more than $20 million for a Venezuelan financial services client in asset forfeiture cases litigated in the Districts of Puerto Rico and Massachusetts.°
  • Civil RICO and securities fraud claims against business investor: Defended the seller of a Florida-based start-up business against post-M&A claims of civil RICO, securities fraud and common law fraud, valued in excess of $15 million.°
  • Asset forfeiture cases for Korean distributor: Recovered substantial seized assets from Florida authorities on behalf of a Korean enterprise with distribution operations in Miami and the Caribbean, securing the full return of the assets.°
  • Pharmaceuticals sales asset recovery: Represented a distributor of generic pharmaceuticals in proceedings seeking the return of millions of dollars subject to forfeiture for healthcare kickbacks.°
  • Real estate securities litigation: Represented an international real estate developer against multimillion-dollar securities fraud and other claims brought in Florida state court by an investor.°
  • Return of forfeited assets for Trinidadian financial services client: Represented a Trinidadian financial services company in seeking the return of a multimillion-dollar asset in federal ancillary forfeiture proceedings.°
  • High-value fraud defense: Defended a multinational against fraudulent misrepresentation and securities fraud claims brought by a former senior manager in connection with an executive profit-sharing plan.°
  • Failed accounting software implementation dispute: Represented a multibillion-dollar financial services firm in a lawsuit against a global software provider. Minutes before opening statements to the jury, the case was resolved for more than seven times the defendant's highest previous offer.°
  • Hundreds of millions of dollars sought from Brazilian bank: Defended a major Brazilian bank against infrastructure claims for more than $800 million, including the successful defense of an appeal of dismissal on forum non conveniens grounds.°
  • Wireless email technology litigation: Defended a patent holder against claims brought by alleged former partners for a share in more than $600 million in settlements and royalties.°
  • Theft of trade secrets lawsuit: Represented a former executive and industry innovator in a lawsuit valued at more than $300 million for the theft of his plan to create a new business line, ultimately resulting in a settlement to the client's advantage.°
  • Construction defect and consumer fraud class action: Represented a leading national homebuilder in resolving a class action that ultimately saved the client nearly $150 million in anticipated damages and attorneys' fees.°
  • High-value products liability and consumer fraud claims: For one of the largest manufacturers of ink, pursuing claims against international and domestic defendants for consumer fraud, misrepresentations and products liability valued at approximately $20 million.°
  • International post-deal dispute: Defended a Spanish global telecommunications and infrastructure company against post-M&A claims arising from alleged breaches of representations, warranties and covenants, valued at nearly $10 million.°
  • Multijurisdictional fiduciary duty and conspiracy litigation: For the U.S. subsidiary of a global Spanish conglomerate, pursued claims for breach of fiduciary duty, civil conspiracy, and aiding and abetting; after a seven-day trial, the jury returned a verdict of full liability.°
  • Asset recovery against Venezuelan telecommunications provider: For a publicly traded Spanish conglomerate, brought claims against a Venezuelan company for more than $5 million, resulting in a favorable resolution despite likely collection difficulties.°
  • M&A Hospitality Dispute: Represented multinational Spanish hospitality enterprise in claims for breaches of representations and warranties in connection with the purchase of a New York City hotel.°
  • Defense of product defect and fraud claims: Defended one of the largest manufacturers of ink in an action brought by a former customer valued at more than $2 million, plus punitive damages, ultimately obtaining a dismissal with prejudice.°
  • Discovery proceedings in aid of foreign litigation: Obtained § 1782 relief and related discovery for an Argentina-based beneficiary of an El Salvador-based individual, in aid of anticipated trust and related litigation in Panamanian courts.°

°The above representations were handled by Mr. Mamounas prior to joining Greenberg Traurig, P.A.

Recognition & Leadership

  • Listed, Best Lawyers in America guide, International Arbitration - Commercial, 2021-2024
  • Listed, Benchmark Litigation, "Litigation Star," 2022-2023
  • Listed, The Legal 500 Latin America Guide, "Latin America: International – City Focus: Miami," 2022
  • Listed, Latin Lawyer, "Latin Lawyer 250 - Practice Recognition: Arbitration," 2022-2024
  • Team Member, Global M&A Network’sAmericas M&A Atlas Awards, “Latam Deal of the Year” for Quinto Andar acquires Navent Group, 2023
  • Listed, Florida Super Lawyers Magazine, 2018-Present
  • Listed, Daily Business Review, "Professional Excellence Rising Star Award," 2016
  • Listed, Florida Super Lawyers Magazine, "Rising Star," 2012-2017
  • Immediate Past Co-Chair, American Bar Association (ABA) Section of International Law, International Mediation Committee
  • Advisory Board Member, Posse Foundation – Miami
  • Alumni Board Member, University of Miami Law Review
  • Brazilian-American Chamber of Commerce
  • Dade County Bar Association, Young Lawyers Section
  • Federal Bar Association
  • Miami International Arbitration Society
  • The Florida Bar, Business Law Section and International Law Section
  • The Florida Bar, International Litigation and Arbitration Conference, Steering Committee


  • J.D., cum laude, University of Miami School of Law
  • A.B., summa cum laude, Cornell University
  • Florida
  • English
  • Spanish
  • French
  • Greek
  • German