AT&T Corp has decided to offer for sale a 66% stake in its leasing subsidiary AT&T Capital Corp. That represents 30.88m shares, and would leave AT&T with 20%, down from its present 86%. AT&T Capital said the request was made in a letter from AT&T which says the offering should be completed as soon as possible if that is the way it has to be, but the letter also urged AT&T Capital to continue to explore private sale alternatives to get shot of the thing completely if at all possible. The company expects to be able to file a registration statement with the Securities & Exchange Commission by the end of May. The proceeds of the offer would be used to reduce AT&T’s debt.