Select Software Tools Inc, the Irvine, California modeling tools maker, has failed to sign a deal on its proposed merger with Base Ten Systems Inc, a Trenton, New Jersey medical systems developer. Thomas Gardner, Base Ten’s CEO, said the companies had failed to agree to mutually acceptable terms due to constraints outside our control. The merger’s failure is a blow to Select, which had entered the negotiations seeking a stronger-looking balance sheet according to senior VP, Dave Norris (CI No 3,632). Select has been fighting a protracted battle to reverse failing sales and, reputedly, worsening relations between customers and its service arm.