My pups are here a minimum of 10-12 wks and longer if necessary. That decision is based on the overall health of the puppy at 10 wks of age. I make my decision at that time. And my decision is always made in the best interest of the puppy. I will evaluate each puppy at 10 weeks, taking into consideration how well they did with the weaning process, their vaccinations, if they are eating well on their own and whether I feel they are able to transition to their new home without any episodes of hypoglycemia. I will not keep them longer than I have to but I also will not let them leave until they are 100% ready.