Gabriel A. Quintero-O'Neill

María Elena González-Calderón is a top attorney recognized by Best Lawyers in the practice area(s) of Corporate and M&A Law. María Elena, who practices law in San Juan, Puerto Rico, has been recognized since 2025. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which María Elena is held by other top lawyers in the same geographic and legal practice area.

Julio Pietrantoni is a top attorney recognized by Best Lawyers in the practice area(s) of Banking and Finance Law and Corporate and M&A Law. Julio, who practices law in San Juan, Puerto Rico, has been recognized since 2015. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Julio is held by other top lawyers in the same geographic and legal practice area.

Alfredo Alvarez-Ibáñez is a member in the Corporate Department. He has been with O’Neill & Borges since 1996. Alfredo’s practice is concentrated in various areas of commercial law and creditors’ rights, including real estate, commercial lending, secured transactions, asset-based finance, and complex out-of-court workouts and restructurings, representing both local and U.S.-based financial institutions and businesses. Alfredo’s practice also involves c...

Sonia Colón is a top attorney recognized by Best Lawyers in the practice area(s) of Insolvency and Reorganization Law and Litigation. Sonia, who practices law in San Juan, Puerto Rico, has been recognized since 2020. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Sonia is held by other top lawyers in the same geographic and legal practice area.

Mr. Muñiz represents clients in all phases of tax controversy and litigation matters, from tax audits and examinations through administrative appeals and court proceedings. He actively participates in multiple tax litigations representing clients on wide arrays of tax challenges, including: municipal license tax, income tax, personal property tax and construction excise tax deficiency procedures. He also has extensive experience representing taxpayers during the real property tax asses...

Mayra Cristina Artiles Fonseca is an experienced attorney in the Corporate and Commercial Practice Group where she has successfully represented clients in a wide array of commercial and corporate transactions and disputes. Having also litigation expertise, Mayra provides comprehensive counsel to companies of all sizes on various corporate matters (from both a transactions and dispute resolution approach), helping them navigate complex legal landscapes with confidence and strategic insight. Ma...

Mauricio Muñiz-Luciano is a top attorney recognized by Best Lawyers in the practice area(s) of Competition / Antitrust Law and Litigation. Mauricio, who practices law in San Juan, Puerto Rico, has been recognized since 2021. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Mauricio is held by other top lawyers in the same geographic and legal practice area.

Maité Medero is a top attorney recognized by Best Lawyers in the practice area(s) of Labor and Employment Law and Litigation. Maité, who practices law in San Juan, Puerto Rico, has been recognized since 2019. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Maité is held by other top lawyers in the same geographic and legal practice area.

Ms. Vélez' practice is focused on advising clients on the tax treatment of corporate transactions and reorganizations, as well as assistance in devising tax-efficient corporate structures for new or existing Puerto Rico operations. She has worked extensively with the Puerto Rico tax and industrial incentives acts and provisions relative to U.S. income taxation of international operations, as well as the Puerto Rico and U.S. taxation of investment income, including government obligation...

Juan Ramón Cancio-Ortiz is a top attorney recognized by Best Lawyers in the practice area(s) of Banking and Finance Law, Corporate and M&A Law and Structured Finance Law. Juan Ramón, who practices law in San Juan, Puerto Rico, has been recognized since 2021. This recognition is based on an exhaustive peer-review survey, reflecting the high esteem in which Juan Ramón is held by other top lawyers in the same geographic and legal practice area.