Marcos Fernández De Lavalle is an associate at Posse Herrera Ruiz since 2024. His professional practice focuses on customs and international trade law.

Marcos has experience providing legal support in matters involving customs, foreign exchange, tax law, and trade defense. Marcos has assisted in the establishment and modification of various types of customs warehouses, as well as in operations related to import and export requirements, tariff classification of goods, customs valuation, and compliance with rules of origin to access benefits under trade agreements such as Free Trade Agreements (FTAs). He has also supported responses to information requests issued by the customs authority and participated in matters related to antidumping investigations.

Before joining Posse Herrera Ruiz, Marcos participated in the John H. Jackson Moot Court Competition on WTO Law, an international competition focused on trade law. He was a semifinalist in the global rounds, held in Geneva, Switzerland, as part of the only team from the Americas to reach that stage.