Seiko Group (セイコー・グループ Seikō Gurūpu?) is a Japanese corporate group consisting of three core companies Seiko Holdings Corp. (Seiko), Seiko Instruments Inc. (SII) and Seiko Epson Corp (Epson). They were independent companies linked together by the common thread of timepiece technology. Although they have some common shareholders including the key members of the Hattori family, the three companies in the Seiko Group are not affiliated. They are managed and operated completely independently. Epson has established its own brand image and rarely uses "Seiko."
Seiko Watch Corp., a subsidiary of Seiko Holdings Corp., markets SEIKO watches while Seiko Instruments Inc. and Seiko Epson Corp. manufacture their movements.
On January 26, 2009, Seiko Holdings and Seiko Instruments announced that the two companies will be merged on October 1, 2009 through a share swap. Seiko Instruments became a wholly owned subsidiary of Seiko Holdings on October 1, 2009.
- Seiko Holdings Corporation (SEIKO, TYO: 8050, headquartered in Tokyo)
- Seiko Watch Corporation (marketing watches)
- Seiko Clock Inc. (development, manufacturing, sales and repair of clocks)
- Seiko Sports Life Co., Ltd. (golf clubs, stopwatches, etc.)
- Seiko Time Systems Inc. (system clocks, etc.)
- Seiko Service Center Co., Ltd. (repair and after service for watches)
- Seiko Business Services Inc. (general affairs & human resources)
- Seiko Precision Inc. (electronic/micromechatronics devices, printers, information equipment, system clocks and production equipment, etc.)
- Seiko NPC Corporation (semiconductors)
- Seiko Jewelry Co., Ltd. (jewelry)
- Seiko Optical Products Co., Ltd. (eyeglasses - lenses & frames)
- Ohara Inc. (specialty optical glass; Seiko owns 32.2% TYO: 5218)
- Wako Co., Ltd. (upscale specialty retailer)
- Cronos Inc. (upscale specialty retailer)
- Seiko Instruments Inc. (SII, Subsidiary of Seiko Holdings, headquartered in Chiba)
- SII NanoTechnology Inc.
- Morioka Seiko Instruments Inc.
- SII Network Systems Inc.
- SII Mobile Communications Inc.
- SII Data Service Corp.
- SII Printek Inc.
- SII Microtechno Inc.
- SII Micro Parts Ltd.
- SII Micro Precision Inc.
- Epolead Services Inc.
- Seiko I Infotech Inc.
- Seiko I Techno Research Co., Ltd.
- Seiko EG&G Co., Ltd.
- City Service Co., Ltd.
- Seiko Epson Corporation (EPSON, TYO: 6724, headquartered in Suwa, Nagano)
- Epson Sales Japan Corporation
- Epson Toyocom Corporation
- Epson Direct Corporation
- Epson Service Corporation
- Epson Atmix Corporation
- Epson Software Development Laboratory Inc.
- Yasu Semiconductor Corporation
- Seiko Epson Contact Lens Corporation
- Seiko Lens Service Center Corporation
- Epson Imaging Devices Corporation
- Orient Watch Co. Ltd.