Tecmo Koei Games Co., Ltd. is a developer.
- Gust Co. Ltd. - Founded 1993
- Koei Tecmo Vietnam - Founded ????
- Koei Tecmo Singapore Pte, Ltd. - Founded ????
- Koei Tecmo Taiwan Co., Ltd - Founded ????
- Koei Tecmo Net, Inc. - Founded ????
- Koei Tecmo Wave Co., Ltd. - Founded ????
- Ruby Party - Founded 1994
- Omega Force - Founded ????
- Team Ninja - Founded 1995
- Team Tachyon - Founded 2007
- Tecmo Koei America Corporation' - Founded 2010
- Tecmo Koei Canada, Inc. - Founded 2010
- Tecmo Koei Europe, Ltd - Founded 2010
- Koei Canada, Inc. - Founded 2009/Defunct 2010
- Koei Europe - Founded 2009/Defunct 2010
- Founded on April 1, 2009, as Tecmo Koei Holdings.
- On April 1, 2010, Tecmo Koei Holdings changed their name to Koei Tecmo Holdings Co., Ltd.
- On February 8, 2011 Tecmo, Inc. and Koei Co. Ltd. merged to form Tecmo Koei Games Co., Ltd..
- On July 1, 2014, Tecmo Koei America Corp. was renamed to Koei Tecmo America Corp.
- On July 1, 2014, Tecmo Koei Games Co., Ltd. was renamed to Koei Tecmo Games Co., Ltd.