http://web2.acbl.org/documentLibrary/play/AlertProcedures.pdf Partnerships do not need to Alert their Stayman bids in order to differentiate between those that promise a four-card major and those that don’t. Opponents may assume that an immediate bid of clubs over a natural notrump opening is conventional, asking opener to bid a four-card major, with no guarantee that responder has a four-card major suit. However, when it becomes evident that the Stayman bidder either does not have or tends not to have a four-card major, an Alert is required at that time.