Antonio has led many complex civil litigation proceedings representing major corporates and financial institutions, particularly regarding the enforcement of financial guarantees, as well as in a wide variety of high profile commercial arbitration proceedings under the ICC, Madrid Chamber of Commerce and CIMA arbitration rules, representing both Spanish and foreign entities, including among others disputes pertaining to price reviews, infrastructure projects, representations and warranties or shareholder agreements. 

Antonio also routinely advises companies as regards potential investment treaty disputes against foreign States regarding their oversees investments. From 2011, Antonio designed the strategy, together with the London office, to initiate an investment-treaty arbitration under the ECT against the Kingdom of Spain on behalf of 14 groups of international investors that invested in the Spanish renewable energy sector. This was the first-ever collective claim brought under the ECT. To date, Antonio has acted for investors of six different nationalities in 12 different cases against the Kingdom of Spain. 

Prior to joining the firm in 2005, Antonio served as a State Lawyer for eight years, representing the Spanish State in various high-profile civil, administrative and criminal cases. Antonio notably handled the civil and criminal liability proceedings arising out of MV Prestige oil spill, the worst ecological disaster in the history of the Iberian peninsula and one of the worst of Europe. Antonio also pursued claims before the International Oil Pollution Compensation (IOPC) Fund in London and the American Bureau of Shipping in New York. 

Antonio is a well-known and reputed lawyer in the Spanish market, routinely advising the general counsels of the main corporates and financial institutions present in the Spanish market on strategic litigation matters key to the businesses they are responsible for. 

Antonio also regularly acts as arbitrator in cases under the ICC or CIMA rules. 

He has been recognised as Best Lawyer in Spain by Expansión (Spanish Financial Times) for his outstanding profile and reputation in the country.