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Agustín Siboldi

Work +541143461000
Estudio O'Farrell

Work Department

Energy & Natural Resources - Telecommunications, Media & Entertainment - Competition/Antitrust - Pharmaceutical & Health


Agustín Siboldi is a partner in Estudio O´Farrell’s Public Law and Economic Regulation Department. 

Mr. Siboldi practice focuses on the following areas related with the economic regulation: antitrust law, either economic concentrations as well as the investigation of anticompetitive practices; telecommunication; hydrocarbons exploration, concession, exploitation, and distribution; gas generation, transport, distribution and commercialization; pharmaceutical products marketing; as well as other sector of the economy with a strong regulatory importance.


He joined Estudio O´Farrell in 1998 and is partner since 2007. He is a professor of ESEADE since 2001 in Economic Regulation (Public Utilities Regulation and Antitrust) as well as at the AADT. He used to teach at the Universidad de Buenos Aires, in Civil and Commercial Contracts.


Spanish, English and Portuguese.


Member of AADT, International Bar Association, Instituto Argentino de Petróleo y Gas, Foro Competencia, City of Buenos Aires Bar, Brazilian-Argentine and Mexican-Argentine Chambers of Commerce.


Law Degree, Buenos Aires University. Post degree in Telecommunications Law, Buenos Aires University. Master´s degree in Business Law, ESEADE. Post degree in Telecommunications, AADT.


Competition and antitrust

Within: Leading individuals

Agustín Siboldi - Estudio O'Farrell

Within: Competition and antitrust

The ‘timely and efficient’ team at Estudio O'Farrell leverages its record in regulatory law to specialise in antitrust issues concerning the energy, pharmaceutical, infrastructure and telecoms sectors, among other areas. Department head Agustin Siboldi, who provides ‘opinions clients can trust’, recently paired up with María Agustina Fanelli Evans to defend Farmacity against allegations of anti-competitive practices regarding medicine sales.

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Within: Leading individuals

Agustín Siboldi - Estudio O'Farrell

Within: TMT

According to clients, Estudio O'Farrell stands out for its ‘unique understanding of the telecoms industry’ and for its ability to ‘leverage its legal and commercial knowledge to provide superior outcomes’. Among its highlights, ‘business-savvy’ group co-head Agustín Siboldi, together with ‘great deal facilitatorRicardo Castañeda, advised Comunicaciones y Consumos on its competitive sales process, which involved two potential acquirers. María Agustina Fanelli Evans co-leads the department and paired up with Siboldi to represent Claro Argentina in several regulatory matters.

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Argentina: Energy and natural resources


Within: Electricity

The ‘definitely top-tier team’ at Estudio O'Farrell is commended for its ability to ‘strike a balance between legal analysis and business needs’ and for its ‘uniquely personalised service’. The practice, which works closely with the public law department, is best known for its track record in administrative law matters — both contentious and non-contentious — and commercial work. Senior partner Uriel O’Farrell (‘proactive with a problem-solving approach’) is highly sought after by energy companies for complex issues and co-leads the department together with Agustina Fanelli Evans (‘solid technical and commercial knowledge’) and Agustín Siboldi. On the regulatory front, the firm provides ongoing advice to Pampa Energía and Compañía General de Electricidad, among others. On the transactional side, the firm advised YPF and YPF Energía Eléctrica on a subscription agreement, which involved the sale of a 24.99% stake in YPF Energía Eléctrica’s shares to EFS Global Energy and GE Capital Global Energy Investments.

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Oil and gas

Within: Oil and gas

Estudio O'Farrell’s oil and gas practice, which sits within the firm’s wider public law and economic regulation department, is best known for its ‘deep experience and knowledge of industry regulation’. Indeed, as one client points out, ‘some of its partners were even involved in the design of the current market regulation’, which is a significant benefit on complex administrative law cases. Senior partner Uriel O’Farrell is a key contact for energy regulation and disputes; he acted alongside public law expert Agustín Siboldi to represent Pampa Energía on the renegotiation of the conditions of the national incentive scheme for the production of natural gas. Axion Energy is also a key client and O’Farrell, Siboldi and Agustina Fanelli Evans advise it on day-to-day regulatory and antitrust issues.

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