WASHINGTON -- Cray Inc. (CRAY) filed to sell 6 million shares of common stock along with 937,500 shares for overallotments, according to a Monday filing with the Securities and Exchange Commission. Cray also registered 250,000 shares for some shareholders. The company won't receive any proceeds from the sale of shares by the shareholders. Cray said it will use the net proceeds from the sale of the 6 million shares for general corporate purposes. The filing didn't specify the selling shareholders or the number of shares offered by each. Needham & Co. and SG Cowen were listed as the underwriters for the offering. Cray said it estimates the value of all the shares registered is about $54.2 million. Cray designs, builds and sells high performance general-purpose parallel computer systems.