Ok let me help you... I feel bad for you.... That is not a short.. A short is a call my broker to get a locate.... Once the broker has located .. I then can start shorting... What selling stock BEFORE the cert is delivered...(done all the time). The cert covers the sale. If the cert is delayed for whatever reason afterT+3 the broker can "buy in". Happens all the time.. In this case if that we're to happen Mimv would be penalized. Got it?