Company History
| May 1963 | NANKAI DENKO CORPORATION was established after the merger of four electrical construction companies, Tokushima, Nankai, Iyo and Kagawa. Established as a business corporation (Kabushiki Kaisha). Four branches in Tokushima, Kochi, Ehime, Kagawa, and the Osaka regional office (current Osaka headquarters) were established. |
|---|---|
| December 1965 | The corporate name was changed to SHIKOKU ELECTRIC CONSTRUCTION CORPORATION. |
| March 1966 | Tokyo regional office (current Tokyo headquarters) was established. |
| May 1973 | Okayama business office was established. |
| November 1979 | The company shares were listed on the First Section of Tokyo Stock Exchange. |
| November 1989 | The corporate name was changed to YONDENKO CORPORATION. |
| November 1992 | Bunri business office was established. |
| November 1994 | Acquisition of the shares of Kochi Create Corporation. |
| October 1996 | Accel Tokushima Corporation was established. |
| February 1997 | Yonko Business Co., Ltd. was established. |
| April 1997 | CADEWA SERVICE Co., Ltd. was established. |
| October 1997 | Accel Matsuyama Corporation and Kagawa Create Corporation were established. |
| February 2006 | Utazu School Lunch Service Co., Ltd. was established. |
| November 2007 | Tokushima City High School PFI Service Co., Ltd. was established. |
| November 2010 | Tokushima Agriculture, Forestry and Fisheries PFI Service Co., Ltd. was established. |
| April 2011 | Ozu School Lunch PFI Service Co., Ltd. was established. |
| March 2012 | Tohoku business office was established. |
| December 2012 | Nio Solar Power Co., Ltd. was established. |
| September 2013 | Yonko Solar Co., Ltd. was established. |
| March 2014 | Kuwano Solar Power Co., Ltd. was established. |
| August 2016 | Kasaoka School Lunch PFI Service Co., Ltd. was established. |
| October 2016 | Ozu School PFI Service Co., Ltd. was established. |
| December 2016 | Matsuyama School Air Conditioning PFI Service Co., Ltd. was established. |
| August 2017 | Seiyo Town Development Service Co., Ltd. was established. |
| January 2018 | Tokushima Prefectural Police PFI Service Co., Ltd. was established. |
| February 2018 | Acquisition of the shares of Arimoto Oncho Corporation. |
| July 2018 | Acquisition of the shares of AI DENKI TSUSHIN Co., Ltd. Corporation. |
| August 2018 | Saijo School Air Conditioning PFI Service Co., Ltd. was established. |
| October 2018 | Acquisition of the shares of RYOUEI SETSUBI KOUGYOU Co., Ltd. |
| November 2018 | Yondenko Vietnam Company Limited was established. |
| August 2019 | Acquisition of the shares of kansaisetubi, Co., Ltd. |
| March 2020 | Acquisition of the shares of Suzuki Architectural Design Office. |
| May 2020 | Kobe and Kyoto business offices were established. |
| April 2021 | Acquisition of the shares of Yokoyama Kogyo Co., Ltd. |
| July 2021 | Okinawa business office was established. |
| December 2021 | Acquisition of the shares of BELTEC Co., Ltd. |
| April 2022 | Transitioned to the Prime Market due to a market segments review by the Tokyo Stock Exchange. |
