Sylvain Justier

Sylvain Justier


Direct : +33 1 42 25 10 62

Mobile : +33 6 84 59 05 59

Fax : +33 1 42 25 10 74

Languages : French / English

SJU web


Competition law, national and european level
Telecommunications & new technologies law
Distribution & commercial law
Energy law
Consumer law
Media law
Advice / Contract negociation / Litigation

Sylvain Justier, who holds a post-graduate Diploma in Commercial and Corporate Law [DESS-DJCE - Diplôme d’etudes supérieures specialisées – Diplôme Juriste Conseil d’Entreprise] from the University of Rennes 1, started his career in January 2001 at the CMS Bureau Francis Lefebvre, working in the Europe, Competition and Economic Regulations Team. He was appointed Manager in the Team in 2006. In 2007, he joined the Antitrust and Regulatory Practice in the Chambers of White and Case LLP.

He has wide experience in competition law and handles numerous antitrust cases before the competition authorities and national courts. He provides a presence on the occasion of dawn raids and contests such operations. He represents applicant and defending businesses in cartel and abuse of dominant position cases, indemnities-based litigation associated with anti-competitive practices (having to date been involved in ten sets of private enfoncement cases in which sums of between several million and hundreds of millions of Euros were at stake). He also becomes involved in merger control, restrictive competitive practice and unfair competition cases.

In addition, he is a recognised expert in a number of regulated sectors, in particular the telecoms, energy and rail transport sectors. In addition to antitrust cases handled within these sectors, he becomes involved in all the problem regulatory issues his clients come up against and assists them with these, especially in the context of penalty proceedings or proceedings for handling disputes being heard before sectoral regulatory bodies (having been involved in numerous proceedings before the ARCEP – French Telecom – and ART - French Rail- regulatory bodies in particular).

Sylvain Justier appears as a recommended practitioner on competition and regulatory law in the whole body of professional guides and frequently addresses major conferences devoted to these fields of activity.

"The "very bright" Sylvain Justier represents clients before the French Competition Authority and French courts in antitrust investigations and litigations, encompassing horizontal and vertical practices as well as distribution law. He has strong experience in the telecommunications sector.'"

(Chambers Europe 2020, Competition/European Law – France - Band 4)

"Sylvain Justier of Magenta Société d'Avocats is described by clients as a "very bright lawyer with a deep understanding of the sector." Justier draws on his expertise in competition law to offer telecoms companies advice on litigations related to abuse of dominance and antitrust investigations. He also assists clients with regulatory mandates.'"

(Chambers Europe 2020, TMT - France - Spotlight Table)