The company filed an amended registration statement, which includes another 18 million shares by its parent company, Infogrames Entertainment, for a total of 27 million shares.
It said it plans to use the net proceeds from the offering, which it estimated at about $35 million, for debt repayment and general corporate purposes. It said it will not receive any proceeds from the sale of stock by Infogrames.
Atari filed a registration statement with the SEC in early August but did not specify how many shares would be sold by the company and its parent.
Atari shares closed at $5.08 Thursday on Nasdaq.