Marco D’Ostuni’s practice focuses mainly on competition law and on regulation in the energy, telecommunications and media sectors.

He has represented clients in some of the leading EU and Italian competition law cases, often in liberalized and heavily regulated sectors. He is widely published on antitrust matters and regularly lectures at numerous conferences and universities.

Marco joined the firm in 2000 and, until June 2001, was based in the New York office. He became partner in 2009. Prior to joining Cleary, Marco was a trainee at an administrative law firm in Naples, from 1996 to 1997. From 1998 to 2000, he was an associate at a major international competition law firm in Brussels.

Notable Experience

  • SKY Italia in civil proceedings started by Conto TV to obtain the suspension of the award to SKY Italia of the Series A football championship TV rights; and in a successful request for interim measures filed against Publitalia ‘80 (Mediaset’s advertising branch) to enjoin the defendant from refusing to accept SKY Italia’s TV advertising. 

  • Telecom Italia before the AgCom in the successful negotiation concerning the Open Access commitments, to address the competitive problems connected to the control of the fixed access network; and in the successful proceedings against Vodafone in the “Numero Fisso” case. 

  • ENI in winning an appeal before the Council of State which led to a 93% reduction of the largest antitrust fine ever issued in Italy; and  in the proceedings before the European Commission concerning an alleged abuse of dominant position in the management and operation of a number of international natural gas pipelines.

  • ENI and Telecom Italia before the IAA, the Italian regulatory authorities and before courts in some of the main cases related to the liberalization, the competition and the regulatory matters in the Italian gas and telecommunications sectors. 

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Selected Activities

  • Former Intern, European Court of Justice


  • “Excessive pricing and copyright industry: still blurred lines?,” Regulating for Globalization, Wolters Kluwer, December 2017.

  • Il Sistema del controllo delle concentrazioni in Italia, G. Giappichelli Editore, July 2017 (M. Beretta co-author).

  • Facebook v Business Competence S.r.l.,Leading Internet Case Law, May 2017.

  • Italy chapter, The Energy Regulation and Markets Review, fifth edition, September 2016 (Luciana Bellia and Giuliana D’Andrea, co-authors).
  • Italy chapter, The Public Competition Enforcement Review, eighth edition, April 2016 (Giuseppe Scassellati‑Sforzolini and Luciana Bellia, co-authors).
  • Chapters on Italy in: The International Comparative Legal Guide to Cartels & Leniency (Global Legal Group, 2008-2013), Getting the Deal Through – Private Antitrust Litigation (Law Business Research, 2003-2014).
  • Italy.” Practical Law Multi-Jurisdictional Guide 2012: Competition and Cartel Leniency. Practical Law Company. (M. Baretta and P. Ferrari co-authors).
  • “Access to Facilities in the Telecommunications Sector,” April 10, 2012, e-Competitions, No45007.
  • Italy.” Getting the Deal Through – Private Antitrust Litigation 2012. 60-67. Law Business Research. (C. Rizza and M. Siragusa co-authors).
  • Italy.” The Public Competition Enforcement Review. June 2011. Law Business Research. (K. Peçi co-author).
  • “I mercati rilevanti dei prodotti e servizi e la regolazione ex ante,” F. Bassan (ed.), Diritto delle comunicazioni elettroniche: Telecomunicazioni e televisione dopo la terza riforma comunitaria del 2009, 2010 (Mario Siragusa, M. D’Ostuni and F. Marini Balestra co-authors).
  • Chapter 19 – Italy.” International Comparative Legal Guide to: Competition Litigation 2009. Global Legal Group Ltd, London (M. Siragusa co-author).
  • Italy.” Getting the Deal Through – Private Antitrust Litigation 2009. Law Business Research (M. Siragusa and G. Rizza co-authors).
  • “La responsabilità civile in materia antitrust (art. 33, comma 2, L. 10.10.1190 n. 287).” Codice Ipertestuale della Responsabilità Civile. Kluwer, 2008. (M. Siragusa and F. Emanuele co-authors).
  • Economia e Diritto Antitrust. Carocci, 2006. Parts I, II and III (L. Prosperetti, M. Siragusa, M.Beretta and M. Merini co-authors).
  • “A Reflection on Some Private Antitrust Enforcement Issues.” Ehlerman and Atanasiu (eds.), “European Competition Law Annual 2006: Enforcement of Prohibition of Cartels”. Hart, 2006 (M. Siragusa co-author).