About Alberto J.
Alberto J. Castaner blends a Puerto Rico upbringing and international study into a legal career that is both maritime and cross-border in nature. He began his academic path at the University of Puerto Rico–Mayagüez, where he earned a B.A. in psychology before moving on to law school at the Interamerican University of Puerto Rico. He later completed an LL.M. in Admiralty and Maritime Law at Tulane University School of Law and earned a certificate in International Commerce in the European Union from Universita Ca’ Foscari in Venice.
Early in his career he worked as a research assistant for the Puerto Rico Court of Appeals in Hato Rey, serving under Hon. Judge Migdalia Fraticelli. That experience offered a grounding in appellate work and Puerto Rico’s judicial processes. He then entered private practice as an associate at Cintron Law Offices in 2004 and within a few years moved into leadership roles.
Since 2008 he has been in a managing role at his firm. He took on the title of managing partner at Castañer & Cía PSC and has handled firm-level responsibilities while continuing to handle client matters. In the same year he became the Puerto Rico territory partner for Trupanion Pet Insurance, a role that places him at the intersection of business operations and regulatory questions outside strictly traditional litigation.
His legal training and professional affiliations reflect a steady interest in maritime and international commerce issues. He served as an adjunct professor of Admiralty and Maritime Law at the Interamerican University of Puerto Rico School of Law in 2013, teaching students the technical and jurisdictional contours of admiralty practice. He is also a proctor in admiralty for the U.S. Maritime Law Association and has been an active member of that association since 2008.
Castaner is admitted to practice in Puerto Rico and holds federal admissions that allow practice before the U.S. Court of Appeals for the First Circuit, the Federal Circuit, and the U.S. Court of International Trade. He maintains memberships that reflect his varied interests, including the Supreme Court of Puerto Rico and the Puerto Rico Manufacturers Association’s Transportation Committee.
His work spans admiralty and maritime disputes, questions arising from international commerce, and transportation-related matters. He combines classroom teaching, court work, and organizational involvement in ongoing practice. He currently practices at Castañer & Cía PSC, where his practice concentrates on admiralty and maritime matters and on transportation and international commerce issues.
