David Efron founded the firm in 1979. He was born in Havana, Cuba on November 16, 1952. Graduate of the University of Miami (BA 1973) and the Interamerican University Law School (Juris Doctor 1975), with graduate law school work at the University of Miami Law School. In 1979, at age 26, in his first jury trial he scored a victory over federal prosecutors. Six months later, on another case, he won his first federal appeal in First Circuit Court of Appeals, reversing the federal district court on a commercial litigation case.

In 1982, he won his first case in the Supreme Court of Puerto Rico in a trademark infringement case, establishing the precedent in Puerto Rico to date on this issue of law, while reversing the Superior Court of San Juan. In 1991 Efron tried to fruition cases which brought record verdicts in two different areas of expertise - a judgment in an eminent domain case in excess of $5 million and a record jury verdict in federal court in a medical malpractice case in Puerto Rico involving a single plaintiff, a record which stood until he himself obtained a larger award in a 1997 and later in a December 2017 jury verdict on another Medical Malpractice case.

In February 1997 his legal team tried in the State Courts of Puerto Rico a brain damage case which resulted in the highest award in the history of the island's courts - $4.8 million. He has been mentioned in connection to legal cases in USA Today, the Associated Press wire, newspapers nationally and locally, radio and television. He has been featured on NBC's Inside America's Courts (Court TV) among several national programs. In 1996 he appeared at televised Senate hearings to successfully oppose the passing of laws for malpractice reform which would have severely affected the rights of victims in Puerto Rico. He has also appeared featured in local and national newspapers as well as in international publications.

Efron is a member of the Commonwealth of Puerto Rico, District of Columbia and State of New York bars and has a (Coral Gables), Florida office. 

Since January 1990, David Efron has also been the head of the family’s real estate holdings and over a dozen active corporations. He presently serves on the Board of Governors (2005-2022) of The Association of Trial Lawyers of America (now American Association for Justice), has been inducted into the prestigious Multi-Million Dollar Advocates Forum (2010) and is a member of the American Bar Association, the Federal Bar Association and a past member of the Board of Directors of the Home builders Association (1992-2002). In the past he has served on AIPAC's National Council ('88-'96) and Executive Committee ('98 - '09); President of UJA of Puerto Rico ('84-'94) as well as Chairman ('83-'84; '95-'01); Served as General Counsel to the Hispanic Caucus of the DNC ('04-'06) and was on the original Board of the Puerto Rico MaxiBasketball Federation, as well as playing on the Puerto Rico Masters National Basketball team 50+ since 2004. He also actively participates in several national political and community charitable organizations. 

David Efron was designated Honorary Consul for Israel in Puerto Rico on November 11, 2013 and his credentials received by the government of Puerto Rico on September 29, 2015. His appointment is through 2022. He is Israel’s first and only Honorary Consul in the United States. He served on the Board of the Consular Corps of Puerto Rico.

Alberto J. Pérez-Hernández manages the day-to-day operations and is also chief legal counsel to Efron Associates, a real estate development group of affiliated companies. Mr. Pérez was born in Havana, Cuba on November 29, 1953. He is a 1977 graduate of Tulane University School of Law in New Orleans, Louisiana. He also did his undergraduate studies at Tulane, receiving a bachelor of science degree in psychology in 1975.

His post-graduate law studies include participation in Harvard Law School's summer programs for lawyers and numerous continuing legal education seminars and conferences. Mr. Pérez is admitted to practice in all courts of the Commonwealth of Puerto Rico and the State of Florida, the United States Court of Appeals for the First Circuit, the United States Court of Federal Claims and the United States District Court for the District of Puerto Rico. He is a member of the Florida Bar (1977), the “Colegio de Abogados de Puerto Rico” (1978), the Association of Trial Lawyers of America now The American Association for Justice (AAJ), where he serves as governor since 2007 until 2013 and the Federal Bar Association. Mr. Pérez has been actively engaged in private practice since graduation. He has substantial experience in the preparation, trial and appeal of a wide variety of civil cases before state and federal courts and government agencies, including the areas of personal injury, medical malpractice, civil rights, construction, insurance and commercial law. He is also thoroughly familiar with all aspects of real estate, financing and commercial transactions.

Etienne Totti del Toro, born in San Juan, Puerto Rico; admitted to bar, 1998, Puerto Rico, U.S. District Court, District of Puerto Rico and U.S. Court of Appeals, First Circuit. EDUCATION: University of Michigan (B.F.A., 1993); Interamerican University of Puerto Rico Law School (J.D., 1997). MEMBER: American Bar Association; Federal Bar Association. LANGUAGES: Spanish and English. PRACTICE AREAS: Contracts, Torts, Media Law and Libel, Litigation, Corporate, Financing, Real Estate, Labor, Administrative Law, Foreclosures, Banking Law, Notary Law.

JUAN M. MASINI is a lawyer specializing in litigation, investigations, international matters, and intergovernmental affairs. He has been an Assistant U.S. Attorney, Principal at the Masini Global Group and served as Assistant Vice President of Legal and Litigation in Puerto Rico for MAPFRE, a multinational insurance company with operations in over 47 countries. As Assistant Vice President he oversaw over 40 employees including the Attorney, Investigator, and Subrogation Sections and internal/external Fraud Unit the Division handled the crux of the state and federal litigation and he was responsible for over $650,000,000 USD in litigation and strategy for all litigation. He also was responsible for all fraud matters and establishing Anti-fraud protocols and programs as well as projects aimed at strengthening the Anti money laundering and Anti-corruption initiatives of the company. 

As Principal at the Masini Global Group he assists and represents companies, businessmen, and individuals on state and federal civil and criminal matters and litigation as well as judicial and corporate strategy. Mr. Masini advises companies, financial institutions, and individuals on legal matters, litigation strategies, international matters, corporate compliance matters, anti-money laundering detection and protocols, and Anti-Corruption/Foreign Corrupt Practices Act (FCPA) matters. Mr. Masini has advised governments on legislation and judicial training. He has been a political consultant on law enforcement and international matters and is considered an expert who is constantly asked to provide training and speak at international forums, television news media and the international press to provide analysis on legal, legislative, diplomatic, international, compliance, and anti-money laundering matters. 

Mr. Masini is a former U.S. Federal Prosecutor serving for over 14 years for the United States Department of Justice (DOD. From 2011-2013 he was the DOJ's Operations Attaché (Deputy Attache) at the U.S. Embassy Mexico City working on criminal investigations and prosecutions on corruption, narcotics, money laundering, and firearms with U.S. law enforcement agencies along with the Government of Mexico and their Sensitive Investigative Unit He also oversaw some of the U.S. Merida Initiative programs on judicial and law enforcement institutional development and Co-Chaired the Embassy Money Laundering Working Group and the U.S. — Mexico Bi-Lateral Illicit Finance Working Group. From 2003-2011 Mr. Masini was an Assistant United States Attorney (AUSA) for the Eastern District of Louisiana in New Orleans, LA where he prosecuted criminal cases involving narcotics trafficking, fraud - white collar crimes, civil rights violations, trafficking in persons, violent crimes, corruption, money laundering, handled investigation and cooperation of international matters, and represented the United States before the U.S. Court of Appeals. Mr. Masini has served as Assistant Counsel at the Executive Office for U.S. Attorneys and Counsel to the Attorney General’s 

Advisory committee in Washington D.C. advising on border, narcotics, violent crimes, civil rights and international matters. Mr. Masini has served as the DOJ Resident Legal Advisor at the U.S. Embassy in Tegucigalpa Honduras and as Intermittent Legal Advisor at the U.S. Embassies in Bogota, Colombia, Bangkok, Thailand and Mexico City, Mexico. Mr. Masini began his career with the Department of Justice as an AUSA for the Southern District of California. 

Prior to becoming a federal prosecutor Mr. Masini served on active duty as a Naval Officer in the U.S. Navy Judge Advocate General's Corps and with the Central Intelligence Agency (CIA). Due to his background and expertise Mr. Masini has created a specialty in international matters and foreign relations. So, in addition to his work overseas, he is routinely sought by the national and international press for his opinions and analysis and is invited to lecture at numerous international forums. He has assisted several countries in restructuring government agencies and drafting and implementing new legislation; coordinated a variety of international diplomacy, investigations, and prosecution matters; and has advised private sector businesses in compliance, negotiations, corporate strategy and legal matters. Mr. Masini studied engineering at Purdue University where he played intercollegiate football and graduated from The Florida State University with a Bachelor's of  Science and Marketing Degree. He obtained his Juris Doctor from the University of Puerto Rico and an L.L.M. in Labor and Criminal Law from the University of San Diego School of Law in San Diego, California.