| 1920 |
Establishment of Chuketsu Katan Corporation |
| 1920 |
Establishment of Hiranuma Nendo Corporation in Edogawa Ward, Tokyo |
| 1920-06 |
Founded: June, Taisho 9 (1920) |
| 1920-06 |
Founded: June, Taisho 9 (1920) |
| 1936 |
Established Chuo Forging Co., Ltd. |
| 1936 |
Established Hankone Shin Dō Co., Ltd. in Edogawa Ward, Tokyo. |
| 1937-12 |
Founded Sankane Nickel & Copper Co., Ltd. in Edogawa Ward, Tokyo in December 1937 (Showa 12) |
| 1943-12 |
Changed company name to Kanto Communication Metals Co., Ltd. in December 1943 (Showa 18) |
| 1945 |
Showa 20 (1945) |
| 1945-06 |
Relocated to Takaoka City, Toyama Prefecture due to war damage in June 1945 (Showa 20) |
| 1945-06 |
New factory established for B.M.C (Bangkok Maria Blue Corporation). |
| 1947 |
Showa 22 (1947) |
| 1947-05 |
Changed company name to Mitsukoshi Metal Industry Co., Ltd. in May 1947 (Showa 22) |
| 1951-09 |
Certified as a Japan Industrial Standards (JIS) authorized factory in September 1951 (Showa 26) |
| 1955 |
Showa 30 (1955) |
| 1972 |
Showa 47 (1972) |
| 1974 |
Showa 49 (1974) |
| 1984 |
Showa 59 (1984) |
| 1984-09 |
Merged with Hokuriku Metal Industry Co., Ltd. and renamed to Sanetsu Metal Co., Ltd. in September 1984 (Showa 59) |
| 1988-12 |
Established Sanetsu Seiko Co., Ltd. in December 1988 (Showa 63), entering forging and machining processing in earnest |
| 1993 |
Establishment of B.M.C (Bangkok Maria Blue Corporation) new factory |
| 1993-07 |
Established Dalian Mitsukoshi Precision Parts Industry Co., Ltd. in Dalian, China. |
| 1993-07 |
Established Dalian Free Trade Zone Mitsukoshi Metal Industry Co., Ltd. |
| 1993-07 |
Established Mitsukoshi Metal (Shanghai) Guangzhou Branch in Guangzhou, China. |
| 1993-12 |
Listed on Nagoya Stock Exchange Second Section in December 1993 (Heisei 5) |
| 1994 |
Heisei 6 (1994) |
| 2000-04 |
Acquired brass wire business from Sumitomo Metal Mining Nickel & Copper Co., Ltd. in April 2000 (Heisei 12) |
| 2001 |
Establishment of Dalian Mitsukoshi Precision Parts Industry Co., Ltd. in Dalian, China |
| 2002 |
Heisei 12 (2000) |
| 2002 |
Establishment of Dalian Customs Zone Mitsukoshi Metal Industry Co., Ltd. |
| 2002-10 |
Merged with Sanetsu Seiko Co., Ltd. and renamed to Precision Factory in October 2002 (Heisei 14) |
| 2003 |
Heisei 13 (2001) |
| 2004 |
Heisei 14 (2002) |
| 2004 |
Heisei 16 (2004) |
| 2005-01 |
Established Mitsukoshi Metal (Shanghai) Co., Ltd. in Shanghai, China in January 2005 (Heisei 17) |
| 2006 |
Heisei 18 (2006) |
| 2006-10 |
Merged with Hokuriku Zinc Co., Ltd. |
| 2006-12 |
E-Mekki registered with the Ministry of Land, Infrastructure, Transport and Tourism's "NETIS" (New Technology Information Provision System). |
| 2007 |
Heisei 19 (2007) |
| 2007-08 |
Relocated and integrated the Chokeiji Factory to the headquarters location. (Current Mekki Minami Factory) |
| 2007-10 |
Acquired all business from Shin-Nittō Metal Co., Ltd. in October 2007 (Heisei 19) |
| 2007-10 |
E-Mekki received the Excellence Award at the 2nd Manufacturing Japan Grand Prix. |
| 2008 |
Heisei 20 (2008) |
| 2009 |
(Heisei 21) |
| 2010 |
(Heisei 22) |
| 2010 |
Established Mitsukoshi Metal (Shanghai) Guangzhou Branch in Guangzhou, China |
| 2010-04 |
Established CK Sanei Co., Ltd. and made the group a holding company. |
| 2011 |
(Heisei 23) |
| 2011 |
Established CK Sanei Co., Ltd. |
| 2011-10 |
October, Heisei 23 (2011): Transition to a holding company system through company split |
| 2011-10 |
Transitioned to a holding company system through company split. |
| 2011-12 |
Transparent fittings received the Good Design Award. |
| 2011-12 |
Established Riken CK JV Co., Ltd. |
| 2012 |
Established Riken CKJV Co., Ltd. |
| 2012-05 |
Established Sanei Metal (Shanghai) Co., Ltd. Shenzhen Branch (closed Guangzhou Branch). |
| 2012-05 |
Established Taiwan Mitsukoshi Co., Ltd. |
| 2012-05 |
100th anniversary of founding. |
| 2013 |
(Heisei 25) |
| 2013-06 |
Acquired manufacturing equipment for tin reflow plating lines and some equipment for special copper alloy wire from Furukawa Electric in June 2013 (Heisei 25) |
| 2013-10 |
Established Riken CK JV Co., Ltd. |
| 2014 |
(Heisei 25) |
| 2015-01 |
Acquired plating wire business from Hitachi Cable Precision Co., Ltd. in January 2015 (Heisei 27) |
| 2015 |
(Heisei 25) |
| 2015 |
100th Anniversary of Founding |
| 2015-03 |
March, Heisei 27 (2015): Conducted a tender offer for Nippon Shinko Co., Ltd. and became a consolidated subsidiary |
| 2015-03 |
March, Heisei 27 (2015): Transferred all shares of Dalian Mitsukoshi Precision Components Industry Co., Ltd. |
| 2015-03 |
Conducted a tender offer for Nippon Shinko Co., Ltd. and made it a consolidated subsidiary. |
| 2015-03 |
Transferred all shares to Dalian Mitsukoshi Precision Components Industry Co., Ltd. |
| 2016 |
(Heisei 25) |
| 2017 |
(Heisei 25) |
| 2017-03 |
March, Heisei 29 (2017): Listed on the Second Section of the Tokyo Stock Exchange |
| 2017-03 |
Listed on the Second Section of the Tokyo Stock Exchange. |
| 2018 |
(Heisei 25) |
| 2018-03 |
March, Heisei 30 (2018): Listed on the First Section of the Tokyo Stock Exchange |
| 2018-03 |
Listed on the First Section of the Tokyo Stock Exchange. |
| 2018-05 |
May, Heisei 30 (2018): Established Nisshin Chikin Co., Ltd. |
| 2018-05 |
Established Nipshin Chikin Co., Ltd. |
| 2018-11 |
November, Heisei 30 (2018): Merged with Sanei Trading Co., Ltd. and Yashima Co., Ltd. |
| 2018-11 |
Merged with Sanei Trading Co., Ltd. and Yashima Co., Ltd. |
| 2019 |
(Heisei 25) |
| 2020 |
(Heisei 25) |
| 2020 |
(Reiwa 2) |
| 2020-04 |
April, Reiwa 2 (2020): Acquired shares of Okinokogyo Co., Ltd. and made it a subsidiary |
| 2020-04 |
Acquired shares of Okino Industry Co., Ltd. and made it a subsidiary. |
| 2020-06 |
Established Taiwan Mitsukoshi Co., Ltd. in June 2020 (Reiwa 2) |
| 2020-07 |
Acquired brass rod and processed product business and brass wire equipment from Hitachi Alloy Co., Ltd. in July 2020 (Reiwa 2) |
| 2020-08 |
Acquired production equipment from JX Metals Kurobe Galva Co., Ltd. in August 2020 (Reiwa 2) |
| 2020-08 |
Transferred production equipment from JX Metals Kurobe Galva Co., Ltd. |
| 2020-10 |
Acquired production equipment from Imperial Metals Co., Ltd. in October 2020 (Reiwa 2) |
| 2020-10 |
Transferred production equipment from Teikoku Metals Co., Ltd. |
| 2021 |
Established Sanei Metal (Shanghai) Co., Ltd. Shenzhen Branch (closed Guangzhou Branch) |
| 2021 |
(Reiwa 3) |
| 2022 |
Established Taiwan Mitsukoshi Co., Ltd. |
| 2022 |
(Reiwa 4) |
| 2022-04 |
April, Reiwa 4 (2022): Transitioned to the Tokyo Stock Exchange Prime Market |
| 2022-04 |
Transitioned to the Prime Market of the Tokyo Stock Exchange. |
| 2022-10 |
Welding saddle joint received the Good Design Award in October 2022 (Reiwa 4) |
| 2022-10 |
Welding saddle joints awarded the Good Design Award. |
| 2023 |
Reiwa 5 (2023) |
| 2023-10 |
Stainless steel piping expansion joint received the Good Design Award in October 2023 (Reiwa 5) |
| 2023-10 |
In October 2023, W Flange II received the Good Design Award |
| 2023-10 |
Stainless steel pipe expansion joints awarded the Good Design Award. |
| 2023-10 |
W-flange II awarded the Good Design Award. |
| 2025-04 |
April, Reiwa 7 (2025): Acquired shares of Mitani Shinko Co., Ltd. and became a consolidated subsidiary |
| 2025-04 |
Acquired shares of Mitani Shinko Co., Ltd. and made it a consolidated subsidiary. |
