| 1918年02月 |
Established in the former Osaka Shosen Building in front of the Yaesu exit of Tokyo as a lighting power equipment and power transmission and distribution contractor “Yamaka Shokai”. |
| 1945年10月 |
Established Sendai Sales office (currently Tohoku power transmission business headquarters) |
| 1948年09月 |
Changed the trade name to “Yamaka Electric Co., Ltd.” |
| 1950年03月 |
Japan’s first 275,000 volt transmission line construction begins Hokuriku trunk line construction |
| 1958年05月 |
Received an order for construction of a transmission line between Danimu Saigon in the Republic of South Vietnam at that time, and became the first Japanese electrical contractor to expand overseas. |
| 1958年07月 |
Established Nagoya Sales Office (currently Chubu Transmission Division) |
| 1959年03月 |
Established Osaka Sales Office (currently Solution Division (Kansai)) |
| 1965年06月 |
Received an order for TEPCO’s Boso line construction, which attracted attention as Japan’s first 500,000 volt transmission line |
| 1974年12月 |
Received an order for new transmission line construction work for the Mekong River development project in Laos, wiring in Vientiane city, and new construction / expansion / repair of each substation. |
| 1976年09月 |
Received an order from Iran for construction of a transmission line with 12 lines and a total length of 900 km. |
| 1986年08月 |
Received an order for optical fiber construction from a domestic electric power company and promoted technological development for the communication information industry. |
| 1988年10月 |
Received an order for Japan’s first 1 million volt transmission line construction work (Gunma Yamanashi trunk line) |
| 1998年03月 |
Increased capital to 823.06 million yen |
| 2006年05月 |
Increased capital to 989.66 million yen |
| 2006年10月 |
Continued to receive orders for 1 million volt transmission line construction work (Minami-Iwaki trunk line) |
| 2007年02月 |
Listed on the Japan Securities Dealers Association (currently the JASDAQ market of the Tokyo Stock Exchange) and increased the capital to 742.55 million yen. |
| 2008年07月 |
Established Ishinomaki Sales Office in Ishinomaki City, Miyagi Prefecture |
| 2008年12月 |
Established Development Division (currently Electric Power Infrastructure Division) |
| 2009年02月 |
Dispatched supervisor to Dar es Salaam, Republic of Tanzania to build transmission lines |
| 2010年08月 |
Established a new equipment center in Zao Town, Miyagi Prefecture |
| 2012年02月 |
Made Tokyo Management Co., Ltd., which operates a building management business, a wholly owned subsidiary |
| 2012年12月 |
Headquarters moved to Toshima-ku, Tokyo |
| 2013年08月 |
Developed “Enark 160”, a tower raising device |
| 2015年12月 |
Concluded a supervisor contract for trunk transmission line construction in Myanmar and implemented construction |
| 2016年06月 |
Received an order for 30 MW large-scale solar construction work from LG CNS Japan Co., Ltd. (Fukushima Prefecture) |
| 2016年08月 |
Received an order from Canadian Solar Project Co., Ltd. for the construction of the Saitama Minano Power Plant, which is a high-difficulty work to be carried out on a steep slope of up to 45 degrees. |
| 2017年08月 |
Obtained a patent right for the tower raising device “Enark 160” |
| 2017年12月 |
Moved Sendai Transmission Business Department (currently Tohoku Transmission Business Headquarters) to the center of Aoba Ward, Sendai City, Miyagi Prefecture. |
| 2018年02月 |
Changed the trade name to “ETS Holdings, Co.,ltd.” |
| 2019年05月 |
Concluded a business alliance agreement with Navik |
| 2019年06月 |
Completed construction of an extra-high voltage substation that receives 154,000 volts at a 55MW solar power plant (Gifu Prefecture) |
| 2019年09月 |
Moved Kansai Sales Office to Higashikoraibashi, Chuo-ku, Osaka |
| 2019年10月 |
Moved Chubu Transmission Division to Shimizu, Kita-ku, Nagoya City, Aichi Prefecture |
| 2019年11月 |
Completed construction of an extra-high voltage substation that receives 154,000 volts at a 62MW solar power plant (Aichi Prefecture) |
| 2021年06月 |
Venture company from Kyoto University that deals with ecosystem surveys |
| 2021年08月 |
Business tie-up with Sunlit Seed Rings Co., Ltd. (Kyoto) |
| 2021年09月 |
Acquired a solar power plant (Ukiha City, Fukuoka Prefecture) |
| 2021年12月 |
Made Iwai Kogyo Co., Ltd. a wholly owned subsidiary |
| 2022年02月 |
Made Yuuki Sangyo Co., Ltd. a wholly owned subsidiary |
| 2022年06月 |
100th anniversary of founding |
| 2024年10月 |
Establishment of our company through share transfer |
| 2025年10月 |
Change the trade name of “ETS Holdings Co.,ltd.” to “ETS Line Co.,ltd.” |
| 2025年10月 |
Change the trade name of “Tokyo Management Co., Ltd.” to “ETSOK Co.,ltd.” |
| 2025年10月 |
Change the trade name of “yuuki Sangyo Co., Ltd.” to “ETS Clear Co.,ltd.” |