Hajime Watanabe is one of the founding partners of STW & Partners. His main areas of practice are antitrust and competition laws, dispute resolution and intellectual property litigation. He also has assisted a number of clients with antitrust aspects in their commercial transactions and the establishment of compliance structures based on his extensive experience in cases in Japan and other jurisdictions.

He obtained an LLB from the University of Tokyo in 1985 and was admitted in Japan to the Daini-Tokyo Bar Association in 1987. He was also admitted to the New York State Bar Association in 1995, and obtained an LLM from the University of Illinois, College of Law, in 1993. Mr Watanabe joined Mori Sogo (now Mori Hamada & Matsumoto) in 1987. He worked at Jenner & Block in Chicago from 1993 to 1995 and at the US Federal Trade Commission in Washington DC in 1995. In 1994 Mr Watanabe was admitted in Illinois (as a foreign consultant) at the Chicago Bar Association and in New York at the New York Bar Association, and he is a member of the American Bar Association and the American Intellectual Property Law Association. He established STW & Partners in 2007.

STW & Partners was established on April 1, 2021 by eight lawyers who left Mori Hamada & Matsumoto to form a cutting-edge new law firm. STW & Partners offers a wide range of legal services, including providing legal advice with respect to corporate management and organization, multinational and cross-border transactions, general corporate matters, complex domestic and international litigation and other dispute resolution matters, insolvency, intellectual property, M&A, finance, and antitrust law matters. By combining the wealth of highly specialized knowledge and experience that each partner at STW & Partners brings to the firm, it can provide innovative legal advice in a flexible and effective manner that is tailored to each case, while maintaining a broad perspective unfettered by a particular field.