Mr. O’Brien focuses his practice on mergers and acquisitions, joint ventures and private equity transactions. He has represented strategic clients, financial institutions and private equity firms in investment transactions for over 30 years. His clients include companies and investors in the Fintech and Life Sciences industries.

Mr. O’Brien also counsels companies in general corporate and securities matters, including financing transactions. He has represented creditors and debtors in the corporate aspects of restructuring transactions, including the issuance and exchange of securities and negotiation of new shareholder arrangements.

Mr. O’Brien has been selected for inclusion in The Best Lawyers in America from 2005 to 2017. He is a member of the New York State Bar Association and the American Bar Association. He has served on the board of directors of the Polytechnic Institute of NYU, the Lincoln Center Consolidated Corporate Funds leadership committee and the board of directors of the Friends of the Highline.