Seikosha (精工舎, Seikōsha) was a branch of the Japanese company Seiko that produced clocks, watches, shutters, computer printers and other devices. It was the root of the manufacturing companies of the Seiko Group.
1881 — Kintarō Hattori opens the watch and jewelry shop "K. Hattori" (Hattori Tokeiten in Japanese; currently named Seiko Holdings Corporation) in the Ginza area of Tokyo, Japan.
1892 — Seikosha is established in Tokyo as the clock manufacturing arm of K. Hattori.
1917 — K. Hattori becomes a company (K. Hattori & Co., Ltd.).
1937 — The watch production division of Seikosha is split off as Daini Seikosha Co., Ltd. (第二精工舎, literally The Second Seikosha).
1942 — Daiwa Kogyo, Ltd. is founded in Suwa, Nagano by Hisao Yamazaki.
1943 — Daini Seikosha establishes a factory in Suwa for manufacturing watches with Daiwa Kogyo.
1959 — Daiwa Kogyo and the Suwa Plant of Daini Seikosha merge to form Suwa Seikosha Co., Ltd. (諏訪精工舎)
1961 — Shinshu Seiki Co., Ltd. is established as a subsidiary of Suwa Seikosha.
1970 — Seikosha is split off from K. Hattori & Co., Ltd., and Seikosha Co., Ltd. is incorporated.
1982 — K. Hattori & Co., Ltd. is renamed Hattori Seiko Co., Ltd.
1982 — Shinshu Seiki is renamed Epson Corporation.
1983 — Daini Seikosha is renamed Seiko Instruments & Electronics Ltd.
1985 — Suwa Seikosha and Epson merge to form Seiko Epson Corporation.
1990 — Hattori Seiko Co., Ltd. is renamed Seiko Corporation.
1996 — Seikosha Co., Ltd. is divided into Seiko Precision Inc. and Seiko Clock Inc.
1997 — Seiko Instruments & Electronics is renamed Seiko Instruments Inc.
2007 — Seiko Corporation is renamed Seiko Holdings Corporation.
1 October 2009 — Seiko Instruments becomes a wholly owned subsidiary of Seiko Holdings.
