Nicolás Fernández Madero was an associate at the firm from 2007 to 2015, and has served as Senior Counsel since 2024.

He specializes in corporate law, banking and finance, capital markets, fintech and blockchain. Prior to joining O’Farrell, he was a Partner at DLA Piper, primarily advising local and international fintech and blockchain companies on their operations and business establishment in Argentina, and also was a Senior Counsel at Mitrani, Caballero & Ruiz Moreno, forming part of the corporate, banking and finance team, were he worked in M&A and capital market transactions. Recognized by The Legal 500 Latam 2024 as a key name of Mitrani Caballero Ruiz Moreno’s banking and finance team, in the practice of fintech and cryptoassets.

In corporate and M&A matters, he advised Sandoz on its carve-out and asset transfer with Novartis; Zhong Lun, representing its client China Zhongyuan Engineering Corporation, on EPC agreements for the Atucha V Nuclear Power Plant; YPF on the JV with Petronas and YPF (Kuala Lumpur and Putrajaya, Malaysia) for the exploration and production of oil and gas in Vaca Muerta (US$1,500 million); the Italian group Eni Gas on the sale of listed shares in Distribuidora de Gas Cuyana S.A. and Distribuidora de Gas del Centro S.A., including a public tender offer (OPA); and HSBC Bank on the acquisition of BNL Bank (US$155 million). He also participated in Bioceres’ acquisition of Union Acquisition Corp.

Nicolás also has extensive experience in banking, finance and capital markets, including syndicated loans, debt restructurings, securitizations, and the issuance and placement of local and international negotiable obligations (ON). His most relevant transactions include the issuance of Series I and II negotiable obligations by Pro Mujer Servicios Financieros S.A. (ARS 570 million) (Jan and Sept 2023); more than 40 YPF negotiable obligations issuances (2012–2015), including local and international exchanges and reopenings; the structuring of financial trusts for infrastructure projects in the energy (ARS 500 million) and railway sectors (ARS 1,500 million); the issuance of negotiable obligations by Telefónica de Argentina (ARS 250 million); and the issuance of the Fideicomiso Financiero Fideiagro – Hexagon HSBC Global Programme (ARS 8 million), among others.

In fintech and blockchain, Nicolás advises on the registration of entities as VASPs (PSAV) and PSPs, tokenization transactions, regulatory compliance for fintech companies and virtual asset service providers, payment card offerings and on-/off-ramp structures. Among notable matters, he advised Agrotoken on tokenization projects (grains, solar energy, land, livestock, oil and gas) (2020–2023) and Nash21 on tokenization of real estate leases (2022). He advised Binance (the world’s largest crypto exchange) on its initial entry into Argentina (2022), RedotPay Hong Kong and YouHodler (Switzerland) on its registration and establishment in Argentina (2024), among others.

He is a lawyer graduated from the Law School of the Catholic University of Buenos Aires.

Recognized by The Legal 500 Latam 2025 as a Recommended Lawyer in the areas of Banking & Finance and Fintech. 

Nominated among the top 50 banking lawyers in Argentina – Who’s Who Legal WWL Banking (2015 to 2023).

He has lectured in the following locations and events: Argentine Securities Exchange Commission, CAFIDAP – Buenos Aires Stock Exchange, CAFIDAP – UCAECE, Argentine Chamber of Corporations, Ambito Summits, The Institute Global, UCEMA, UCA Salta, Public Legal Bar of the City of Buenos Aires, UCA Buenos Aires, University of Buenos Aires.

Author of “Obligaciones Negociables – Ley N° 23.576 (Comentada)” (published October 2025), a 320 pages practitioner-focused book that, as of publication, is the only work capturing the major post-2012 overhaul of Argentina’s public offering regime and the subsequent key reforms to the Negotiable Obligations framework.  He published more than 60 legal publications in, among others, Latin Lawyer, Diario La Ley, Diario el Derecho, Jurisprudencia Argentina, Revista Enfoques, Revista de Derecho Comercial, Periódico Económico Tributario, El Cronista Comercial.