Actually...do something to extremely discourage the dog to come back your way. Hit it with some pepper spray...or some other nasty(unharming) concoction you can think of that will let him know he is not welcome.
This dog isn't what i call a bad dog. It is a 1 year old yorkie who lives half mile down the road half the time and in my neighborhood part of the time. It has been returned more times than i care to count. The owners act like it is everyone else problem to find and return it. I filed a lost report with the humane society so they knew the dog had been found. When! Not if it comes back it will go to the humane society in the next county, to find a better home where someone will watch it better.