- April 1955
- Private business established as Ando Firm in Omachi, Hirosaki City.
- September 1972
- Reorganization implemented to create a stock company called SEINAN Corporation.
- April 1973
- SEINAN Corporation Namioka Plant opened and chosen as a designated agent by Mitsui Co., Ltd.
- April 1977
- SEINAN Corporation Akita Branch opened.
- May 1979
- Industrial waste disposal license obtained by SEINAN Corporation (Aomori Prefecture).
- July 1979
- Shredding plant put into operation at SEINAN Corporation Namioka Plant.
- August 1980
- Headquarters moved to Watoku Industrial Complex in Hirosaki City.Headquarters Plant opened.Aluminum melting furnace put into operation.
- June 1981
- SEINAN Corporation Hachinohe Branch opened.Guillotine shear put into operation.
- June 1983
- Pre-shredder put into operation at SEINAN Corporation Namioka Plant.
- September 1983
- Akita Rinko Scrap Corporation established (separate from SEINAN Corporation).
- April 1984
- Akita Rionko Scrap Corporation Noshiro Plant opened.
- August 1986
- SEINAN Corporation Morioka Branch opened.
- August 1987
- SEINAN Corporation Sendai Branch opened.Shredding plant put into operation.
- August 1989
- Melting reverberatory furnace put into operation at SEINAN Corporation Namioka Plant.
- September 1989
- SEINAN Engineer Corporation established.
- October 1989
- Shredding plants put into operation at Akita Rinko Scrap Corporation.
Shredding plants put into operation at SEINAN Corporation Hachinohe Branch Hachinohe Plant.
- July 1990
- New Metal Corporation established.
- July 1992
- Aluminum rotary furnace put into operation at SEINAN Corporation Hirosaki Headquarters Plant.
- July 1993
- SEINAN Corporation Aomori Branch opened.
- July 1994
- Heavy Media Separation plant put into operation at SEINAN Corporation Hirosaki Headquarters Plant.
- June 1995
- General motor truck transportation license obtained (Tohoku-Ji-Ka No. 342)
- January 1996
- Company name was changed from "Akita Rinko Scrap Corporation" to "Akita Rinko Corporation".
- April 1996
- SEINAN Corporation Koriyama Branch Koriyama Plant opened. Shredding plant and Heavy Media Separation plant put into operation.
- April 1996
- Machine-related patent secured (Patent 2044305).
- June 1996
- Industrial waste disposal license obtained by Akita Rinko Corporation (Akita Prefecture).
- June 1996
- Further industrial waste disposal licenses obtained by SEINAN Corporation (Iwate prefecture).
- October 1996
- Aomori Renewable Energy Recycling Corporation established.
- November 1997
- SEINAN Express Corporation established.
- February 1998
- Industrial waste disposal license obtained by SEINAN Corporation (Sendai).
- March 1998
- SEINAN Corporation Hirosaki Branch Inakadate Plant
opened.Non-ferrous metal hand picking line put into operation.
- July 1999
- Industrial waste disposal license obtained by SEINAN Corporation (Fukushima Prefecture).
- February 2000
- Industrial waste disposal license obtained by Aomori RER (Aomori Prefecture).
- April 2000
- Gasification melting power plant put into operation at Aomori RER.
- December 2001
- SEINAN Corporation Aomori Branch Aomori Plant opened.Shredding plant and Heavy Media Separation plant put into operation.
- February 2002
- Industrial Technology Center (controlled final landfill site) opened.ECO Plaza Aomori opened by Aomori RER in Aomori City.SEINAN Group (5 corporations, 14 offices) obtained ISO14001 certification.
- December 2003
- Industrial Technology Center was absorbed by SEINAN Corporation.
- May 2004
- SEINAN Express Corporation Aomori Office opened.
- June 2004
- SEINAN Corporation Morioka Branch ULTREC Yahaba opened.
- December 2004
- SEINAN Corporation Hirosaki Branch ULTREC Aomori opened.
- July 2005
- SEINAN Corporation Sakata Branch Sakata Plant opened. Shredding plant put into operation.SEINAN Corporation Sakata Branch ULTREC Sakata opened.
- September 2005
- Industrial waste disposal license obtained by SEINAN Corporation (Yamagata Prefecture).
- April 2006
- SEINAN Corporation Aomori Branch Plastic Recycling Plant put into operation. Recycling business (PET bottle) started.
- July 2006
- SEINAN Corporation Sendai Branch Shiogama Plant opened.Shredding plant put into operation.SEINAN Corporation Sendai Branch ULTREC Shiogama opened.SEINAN Corporation Hachinohe Branch ULTREC Hachinohe opened.
- September 2006
- Industrial waste disposal license obtained by SEINAN Corporation (Miyagi Prefecture).
- April 2008
- Recycling business (Plastic container and packaging) started.
- November 2009
- Machine-related patent secured (Patent 4405240).
- April 2011
- SEINAN Corporation Sakata Branch Tendo Plant and ULTREC Tendo opened.
- November 2016
- Akita Rinko was absorbed by SEINAN Corporation.SEINAN Corporation Akita Branch Akita-Rinko Plant opened.SEINAN Corporation Akita Branch Noshiro Plant opened.
- September 2017
- SEINAN Corporation Aomori Branch Plastic Recycling Plant obtained ISO9001 certification.
- April 2018
- Company name was changed from "Aomori Renewable Energy Recycling Corporation" to "SEINAN RER Corporation".
- April 2020
- New Metal Corporation was absorbed by SEINAN Corporation.
- January 2021
- Trademark rights of company logo obtained (Patent No. 6341625, 6341626).
