MCV can reveal that five staff have already accepted redundancy packages, with another key exec still considering his options.
Atari's reduction of overhead further underlines its intention to streamline the business as it prepares to introduce new business models from 2009.
The highest profile departure will be UK managing director Jeremy Wigmore.
Also leaving are Claire Tennant, Roxanna Etemad, Chiara Woolford and David Nelson - variously from admin, PR, marketing and business development.
Sales director Andy Johnson is believed to have also been offered redundancy, but is undecided as yet.
Atari remains committed to its sales and marketing operation in the UK, however, and has a number of key releases due in the second half the year.
These include Driving Theory on DS, Smash Court Tennis on Xbox 360, Family Trainer on Wii, Alone In The Dark on PS3 and the multi-format hope Legendary.