| 1931 |
1931 (Show 6): Founded as Otaki Natural Gas Co., Ltd., engaged in natural gas business |
| 1931 |
Founded as Otaki Natural Gas Co., Ltd., engaged in natural gas business |
| 1935 |
1935 (Show 10): Established Chiba Natural Gas Co., Ltd., expanded into city gas supply mainly in Otaki Town and Mobara City |
| 1935 |
Established Chiba Natural Gas Co., Ltd., expanded into city gas supply mainly in Otaki Town and Mobara City |
| 1935 |
In 1935, expanded from Chiba Prefecture Otaki Town to Mobara City (Chiba Prefecture) |
| 1937 |
1937 (Show 12): Established Gas Chemical Industry Co., Ltd., entered iodine business |
| 1937 |
Established Gas Chemical Industry Co., Ltd., entered iodine business |
| 1938-06 |
Started operation of starch-based iodine manufacturing equipment in Otaki Town, Chiba Prefecture, from June 1938 |
| 1944-09 |
Stopped operation of starch-based iodine manufacturing equipment in Otaki Town, Chiba Prefecture, in September 1944 |
| 1949 |
1949 (Show 24): Listed on the Tokyo Stock Exchange |
| 1949 |
Listed on the Tokyo Stock Exchange |
| 1956 |
1956 (Show 31): Established Otaki Gas Sales Co., Ltd. as a subsidiary mainly for gas supply and sales |
| 1956 |
Established Otaki Gas Sales Co., Ltd. as a subsidiary mainly for gas supply and sales |
| 1956 |
Started gas supply to Tamagawa Mine (Yokohama City, Kanagawa Prefecture) in 1956, operated a gas well on-site for compressed gas production and sales |
| 1957 |
1957 (Show 32): Started supplying city gas as a chemical industrial raw material to Toyo High-Pressure Industry Chiba Plant (now Mitsui Chemicals Mobara Plant), advancing large-scale natural gas development since 1956 |
| 1957 |
Started supplying gas as a chemical industrial raw material to Toyo High-Pressure Industry Chiba Plant (now Mitsui Chemicals Mobara Plant), advanced large-scale natural gas development since 1956, changed company name to Kanto Natural Gas Development Co., Ltd., and Otaki Gas Sales Co., Ltd. to Otaki Natural Gas Co., Ltd. |
| 1959 |
Closed Tamagawa Mine (Yokohama City, Kanagawa Prefecture) in 1959 |
| 1960 |
1960 (Show 35): Started selling LP gas (liquefied petroleum gas) |
| 1960 |
Started selling LP gas (liquefied petroleum gas) |
| 1961 |
1961 (Show 36): Started supplying city gas in Ichihara City |
| 1961 |
Started supplying city gas in Ichihara City |
| 1961 |
Started supplying city gas in Tatsumi-dai, Ichihara City, in 1961, began gas supply in the Bōbu area of Chiba Prefecture |
| 1968 |
1968 (Show 43): Started supplying city gas in Hamano area, Chiba City, and Yachiyo City |
| 1968 |
Started supplying city gas in Hamano area, Chiba City, and Yachiyo City |
| 1970 |
1970 (Show 45): Established Otaki Sangyo Co., Ltd. |
| 1970 |
Established Otaki Sangyo Co., Ltd. |
| 1971 |
1971 (Show 46): Started supplying city gas in Hoda and Toke areas, Chiba City |
| 1971 |
Started supplying city gas in Hoda and Toke areas, Chiba City |
| 1973 |
1973 (Show 48): Completed Chiba Line (Mobara City, Chiba Prefecture to Chiba City, Chiba Prefecture, 33 km long) |
| 1973 |
Completed Chiba Line (Chiba Prefecture Mobara City to Chiba City, 33 km long) |
| 1974 |
1974 (Show 49): Entered construction industry |
| 1974 |
Entered construction industry |
| 1976 |
1976 (Show 51): Established Kanto Construction Co., Ltd., transferred part of construction business |
| 1976 |
Established Kanto Construction Co., Ltd., transferred part of construction business |
| 1978 |
1978 (Show 53): Customer count exceeded 50,000 |
| 1978 |
Customer count exceeded 50,000 |
| 1982 |
1982 (Show 57): Introduced ethylene off-gas as a new gas source |
| 1984 |
1984 (Show 59): Changed listing to the First Section of the Tokyo Stock Exchange |
| 1984 |
Changed listing to the First Section of the Tokyo Stock Exchange |
| 1985 |
1985 (Show 60): Established KNG America, Inc., engaged in oil and gas development in the U.S. |
| 1985 |
Established KNG America, Inc., engaged in oil and gas development in the U.S. |
| 1989 |
1989 (H1): Completed New Yachiyo Line (Mobara City, Chiba to Yachiyo City, Chiba, 68 km long) |
| 1989 |
Completed New Yachiyo Line (Chiba Prefecture Mobara City to Yachiyo City, 68 km) |
| 1991 |
1991 (H3): Introduced industrial LNG (liquefied natural gas) as a new gas source |
| 1992 |
1992 (H4): Changed company name from Otaki Natural Gas Co., Ltd. to Otaki Gas Co., Ltd., customer count exceeded 100,000 |
| 1995 |
1995 (H7): Acquired municipal gas business from Narutou Town (now Sanmu City) in Sanmu District, started supplying city gas |
| 1996 |
1996 (H8): Listed on the Second Section of the Tokyo Stock Exchange |
| 2003 |
2003 (H15): Customer count exceeded 150,000 |
| 2006 |
2006 (H18): Completed Sodegaura Marine Line (Sodegaura City, Chiba to Ichihara City, Chiba, 14 km), introduced BOG (Boil-Off Gas) as a new gas source, obtained ISO 14001 certification at all facilities |
| 2006 |
Completed Sodegaura Marine Line (Sodegaura City, Chiba to Ichihara City, Chiba, 14 km), introduced BOG (Boil-Off Gas), obtained ISO 14001 certification at all facilities |
| 2007 |
2007 (H19): Made Japan Natural Gas Co., Ltd. a subsidiary |
| 2007 |
Made Japan Natural Gas Co., Ltd. a subsidiary |
| 2008 |
2008 (H20): Customer count exceeded 160,000 |
| 2014 |
Established K&O Energy Group Inc.: (Kanto Natural Gas Development Co., Ltd. and Otaki Gas Co., Ltd. merged), listed on the First Section of the Tokyo Stock Exchange (now listed on the Prime Market) |
| 2017 |
2017 (H29): Customer count exceeded 170,000 |
| 2017 |
Relocated K&O Energy Group Inc. headquarters from Tokyo to Mobara City, Chiba Prefecture |
| 2018 |
2018 (H30): Merged with Kanto Construction Co., Ltd. |
| 2018 |
2018 (H30): Merged with Otaki Sangyo Co., Ltd., started power retail business |
| 2018 |
Merged with Kanto Construction Co., Ltd. |
| 2018 |
Made WELMA Co., Ltd. a subsidiary |
| 2021 |
2021 (R3): Established KNG Farm Inc. to enter plant factory business |
| 2021 |
Established KNG Farm Inc., entered plant factory business |
| 2022 |
2022 (R4): Reorganized with Japan Natural Gas Co., Ltd. (now K&O Iodine Co., Ltd.) to consolidate natural gas business within the group |
| 2022 |
2022 (R4): Completed Nohana Pipeline (JERA Futtsu LNG Terminal to Anesaki Power Plant, 31 km) |
| 2022 |
Reorganized with Japan Natural Gas Co., Ltd. (now K&O Iodine Co., Ltd.) to consolidate natural gas business within the group |
| 2023 |
2023 (R5): Acquired Goso Mining Co., Ltd. and merged with Goso Boring Co., Ltd., renamed as KNG Well Tech Co., Ltd. |
| 2023 |
Merged Japan Mining & Development Co., Ltd. into its subsidiary, KNG Well Tech Co., Ltd., and changed company name |
