We all no all hunters aren'r ethical or always do the right thing,but legally he is not in the wrong and if you piss him off by asking him to move his stand back his response will probably piss you off and then the nest thing you know id that you will both be in a pissing match and neither will want to back down and you'l both wind up making it where the area won't be worth hunting for either party.Even if the deer are crosiing from your property to his they just don't pop up out of the ground on your property line they must be coming from farther in just set up farther inside your property,also remember if the deer cross from yours to his they surely cross from his to yours,now for safety reasons I would let him no the locations of some of the stands on your property so he won't shoot toward them and it will also help detere him from maybe giving in to the temptation to shoot that deer on your proprty if he knows someone from your camp may be hunting very close to where he is.Bottom line id he is within his rights and until he breaks the law you will have to come to terms with it,like alot of people on here have said you should try to form some kind of relationship with him and get to know him first.I hunt where i have others hunter on the property line and I can see deer on their property and we get along fine.