March 1998In partnership, Yoshitaka SONODA, as president, and Yoshinori KOBAYASHI founded the firm in Koto Ward, Tokyo, at the Time 24 Office Building.
May 2001Relocated to the Shinjuku Sumitomo Building.
December 2004Relocated to the Shinjuku Mitsui Building.
January 2015Firm divided into SONODA & KOBAYASHI Intellectual Property Law (Yoshitaka SONODA as managing partner) and SONODA & Kobayashi IP SERVICES Inc. (Yoshitaka SONODA as CEO).
July 2015Akira FUJII, Toshiyasu ISHIOKA, Yoshitaka TOGASHI, and Kimio SATO joined as partners, Yoshinori KOBAYASHI serving as counsel.