A federal judge has rejected HP's (HPQ.N) bid to dismiss a lawsuit claiming that it intentionally designed its all-in-one printers to be unable to scan or fax when they are low on ink, as a means to increase profit by boosting ink sales. Customers in the proposed class action said HP concealed how its printers enter an "error state" when low on ink, disabling scanning and faxing functions that do not require ink, and forcing them to buy unnecessary, high-margin ink cartridges.