Information in the game database is updated periodically. Below, you'll find that information compiled as pertains to Ertain. The company may be involved as a publisher, developer or both.
Air Traffic Chaos [September 9, 2008]
Aquarium by DS [March 14, 2008]
Artist ni Narou! Kigaru ni Sketch [April 28, 2010]
Artist ni Narou! Minna no Nurie Inu-Hen [December 16, 2009]
Artist ni Narou! Minna no Nurie Joukyuu-Hen [January 13, 2010]
Artist ni Narou! Minna no Nurie Musha-Hen [February 3, 2010]
Artist ni Narou! Minna no Nurie Neko-Hen [January 6, 2010]
Artist ni Narou! Minna no Nurie Shokyuuhen [December 9, 2009]
Fantasy Aquarium by DS [December, 2007]
Paint by DS 
Monster Summoner [July 15, 2004]
Warriors of the Lost Empire [unknown]
There are numerous companies in the industry, and their names change like the weather. The information above is not particular about the finer details. Acquisitions are common, so companies with no recent listings may still be developing games under a new name. For example, DMA Design currently has a Rockstar name. Do you know of a title that is not listed above but should be? Be sure and let a staff member know. You can contact staff if you click here.