I just found this many months after you posed your question. Did puppy stop play biting? When I got my pug puppy, my daughter told me to do what their dog mom would do to stop her pups from biting and snapping. A dog mom will give a sharp yelp like when hurt and pick up her pup in her mouth and give them a bit of a toss aside. The puppies do get the message "oops I crossed a line and hurt my sibling!" I was very surprised when I responded that way by sharp Ouch! sound and picking him up by his scruff to move him away from me he got the message. It only took a couple of times and then he learned to only play softly.