Mr. O’Brien is an associate in Davis Polk & Wardwell’s Corporate Department and works in the London office. Since joining Davis Polk in 2000, he has worked on mergers and acquisitions, capital markets and credit transactions in New York, London and Madrid.

Among his recent M&A transactions, he has advised bidders in connection with several public and private company auctions; Royal Caribbean on its acquisition of Pullmantur, a Madrid-based cruise and tour operator, for €430 million in cash and the assumption of €270 million of net debt; Morgan Stanley on the $2.5 billion sale of its aircraft leasing business to Terra Firma; Julius Baer on its CHF 5.6 billion acquisition of three private banks and an asset manager from UBS; Telefónica on its merger with Terra Networks; Novo Nordisk on the restructuring of its business relationship with Aradigm, including asset purchases and entry into two amended licensing agreements; a U.S. private equity fund on its investment in a European communications company; and Yahoo! on its investment in and exit from Sonera Zed.

Among his recent capital markets transactions, he has advised Codere on three high-yield bond offerings and its IPO; Cairn India on an equity private placement; BBVA on its benchmark Rule 144A/Regulation S covered bond offering; Julius Baer on an underwritten rights offering, which raised approximately CHF 2.45 billion in net proceeds that were used to finance a portion of the acquisition purchase price paid to UBS for the acquisition listed above; Corporación Dermoestética on its €137 million initial public offering; the underwriters on Cintra’s €1.54 billion initial public offering; the underwriters on Telecinco’s €753 million initial public offering; and Ashtead on its £120 million high-yield bond offering.

His pro bono practice has included several asylum and immigration matters.

Mr. O’Brien graduated from the University of Virginia in 1996 and in 2000 received his J.D., magna cum laude, Order of the Coif, from Georgetown University Law Center, where he was a member of the Georgetown Law Journal. He is admitted to the bar of New York and is fluent in Spanish.