| November 1942 |
Miura Shipbuilding Co., Ltd. founded Small ship manufacturing and repair business established at Higashiuraga 2-chome, Yokosuka |
|---|---|
| March 1957 | Uraga Dock Co., Ltd. (currently known as Sumitomo Heavy Industries, Ltd.) joined in managing operations |
| January 1962 | Shifted to ship building and repair business at the Uraga Heavy Industries Co., Ltd. (name changed from Uraga Dock) Uraga Shipyards |
| October 1968 |
Uraga Shipping Operations Co., Ltd (Uraga Heavy Industries) established Began land/ocean transportation and longshore work as well as industrial waste disposal businesses |
| December 1972 | Began ship building and repairs, bridge and steel structure construction businesses within the Sumitomo Heavy Industries Co., Ltd. Oppama Shipyards |
| February 1978 |
Sumiju Yokosuka Ironworks Co., Ltd. established (by Sumitomo Heavy Industries) Began machinery and steel structure manufacturing and installation business |
| January 1981 | Headquarters moved to 4-7 Uraga-cho, Yokosuka-shi |
| April 1989 | Uraga Shipping Operations Co., Ltd. and Sumiju Yokosuka Ironworks Co., Ltd. absorbed and merged and name changed to Sumiju Yokosuka Kougyo Co., Ltd |
| December 1995 |
Sumiju Technica Co., Ltd. established (by Sumitomo Heavy Industries)
|
| October 2000 |
Sumiju Technica Co, Ltd. absorbed and merged and headquarters moved to current location Yokosuka/Okinawa Base offices opened |
| August 2017 | Special Construction Business - Minister of Land, Infrastructure, Transport and Tourism Authorization (registration of the Okinawa Office) |
| October 2020 | Okinawa office relocated |
