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Santiago del Rio

Work +5411 4310 0100
Marval, O'Farrell & Mairal

Work Department

Competition / Antitrust


Santiago specialises in competition law and has recently handled merger control matters for companies in the software, oil and gas, textiles, pharmaceuticals, automotive, tobacco and air transportation sectors. He also represents companies in antitrust investigations, as well as in challenges to decisions before the appellate courts and Supreme Court of Justice. He has recently advised companies that have been investigated due to abuse of dominant position and cartels in the fuel, software and genetic engineering sectors. He has also assisted companies with setting out their internal competition policies and advised their internal counsels on competition matters.


Santiago was seconded to Spanish law firm Uría Menéndez for a year, where he handled both European Union and Spanish competition matters in the firm's Brussels and Madrid offices.


English & Spanish


He participated in the International Business Transactions exchange program with Southwestern University, trained at the Argentine Treasury Department and is currently a student of the Postgraduate Program of Economics for Competition Law at King’s College University. In 2009 he was a member of the team that won an award from the City of Buenos Aires Bar Association for an essay on the definition of control under Argentine Antitrust Law.


Competition and antitrust

Within: Next generation lawyers

Santiago del Rio - Marval, O'Farrell & Mairal

Within: Competition and antitrust

Put simply, Marval, O'Farrell & Mairal is ‘clearly the best firm in Argentina for antitrust’, with its ‘highly effective advice’, ‘agile and client-oriented service’ and ‘technically solid team’ all striking the right note with clients. Standing out as its key assets are its ‘top-tier lawyers’, who are widely commended for their ‘proactive approach’ and ability to ‘keep constantly up-to-date with industry issues’. Most notably, department head Miguel del Pino is a ‘titan in the area’, while newly promoted partner Santiago del Rio is ‘thorough and knowledgeable’ with a ‘strong ability to simplify complex scenarios’. Excelling in merger filings, investigations and compliance work, the practice also leverages the firm’s wider full-service offering to bring ‘deep industry and cross-practice expertise to all cases’. On the transactional side, del Pino is acting for both ChemChina and Syngenta on the local aspects of their headline $43bn merger. On the contentious side, a major international bank turned to the firm to represent it in the Argentine Competition Commission (CNDC)’s high-profile investigation into alleged collusion and abuse of dominance in the management of the VISA card system – del Rio led that work. Senior partner Alfredo O’Farrell and experienced associate Gabriela Ariel Irizar are also central figures in the group.

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Argentina: Cartels

April 2019. By Santiago del Rio, Partner

This country-specific Q&A provides an overview to cartels laws and regulations that may occur in  Argentina . This Q&A is part of the global guide to Cartels. [Continue Reading]

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