Spatial design began for Tanseisha when our founder, WATANABE Masaji first started remodeling the interior of the newly bustling department stores in Ueno, Tokyo after WWII.
For over seventy years since this humble origin, we have continued to hone our skills and creativity, expanding the field of the general display industry through a multitude of achievements such as our pavilion at the Expo ’70 world fair held in Osaka, the turning point of our company’s history.
When we moved our headquarters to Shinagawa, the doorway of Tokyo, we did so with the intention of it being “the gateway to future design,” and we continue to create space for imaginations to grow while drawing power from our ability to read the times.

October 1946Founded by WATANABE Masaji (Yanaka, Shitaya-ku).
October 1949The original company name Sanko Co., Ltd. was established in Marunouchi, Chiyoda Ward, Tokyo (later the trade name was officially changed to Nikki Co., Ltd.).
December 1959Reincorporated under the current effective name TANSEISHA Co., Ltd.
Headquarters relocated to Kanda Tsukasamachi, Chiyoda Ward, Tokyo.
November 1961Headquarters completed (Yushima, Bunkyo-ku).
February 1964Osaka office established (currently the Kansai branch).
September 1966Registered as contractor (Tokyo Gubernatorial Registration).
March 1967Tanseisha Kosakusho Co., Ltd. founded (currently Tansei TDC Co., Ltd.).
May 1969Registered as contractor (changed to Ministerial Registration).
January 1971Sapporo office established (currently the Sapporo branch).
December 1972Fukuoka office established (currently the Kyushu branch).
April 1974Tohoku office established.
June 1975Registered as an office of a first-class architect (Tokyo Gubernatorial Registration).
November 1978TANSEISHA Co., Ltd. (trade name officially changed from Nikki Co., Ltd. in July of same year) merges with TANSEISHA Co., Ltd. to carry on as a display/decorative design business.
November 1978Tansei Business Co., Ltd. founded.
December 1978Headquarters completed (Ueno, Taito-ku).
September 1983Over-the-counter shares registered with the Japan Securities Dealers Association.
April 1984Tansei Information Institute Co., Ltd. founded (currently Tansei Institute Co., Ltd.).
December 1984Nagoya office established (currently the Nagoya branch).
March 1987Shares listed on the Second Section of the Tokyo Stock Exchange.
February 1997Tansei Display Co., Ltd. founded.
April 1997 Obtained the Real Estate Trader License (Tokyo Gubernatorial Registration).
March 2000Shares listed on the First Section of the Tokyo Stock Exchange.
August 2001ISO14001 certification acquired.
April 2002Game Co., Ltd. (currently JDN Inc.) becomes subsidiary.
June 2003TANSEI CREATIVE DESIGN CO., LTD. (Shanghai, P.R.China) founded.
March 2004Tansei Humanet Co., Ltd. founded.
August 2005Beijing Tansei Co., Ltd. founded.
October 2006T&T Co., Ltd. founded.
December 2006Obtained Privacy mark usage permit.
September 2015Headquarters completed (Konan, Minato-ku).
April 2016Transitioned to a company with audit and supervisory committee.
April 2022Transitioned to Prime Market, new market segment of Tokyo Stock Exchange.