公明黨
Natsuo Yamaguchi became the party's leader on 8 September 2009 after the party and their coalition partner LDP suffered a major defeat in the 2009 general election and became an opposition party since 1999. New Komeito lost ten seats, including that of party leader Akihiro Ota and general secretary Kazuo Kitagawa. On 8 September 2009, Yamaguchi replaced Ota as president of New Komeito.