Thanks for your replies. We handle intruder and fire alarms for over 5,000+ premises UK-wide including a large retail chain with over 400+ stores and it's the retail stores that I have the confusion with. We don't get duplicates on every activation from every store but I have known to receive a single activation, followed by several duplicates and finally a verified which was later confirmed as a break-in, and we've also had a single followed by duplicates and that also was a confirmed as a break. So my question really is, are the duplicates an indication that a break-in is taking place without receiving a verified signal? The stores are using webway.