I see he's a Dutch Shepherd, they must have floppy ears. I'd hate to think a Lab could have that much fun chomping on somebody . . .
A Lab can chomp; according to a poster that I saw in a vet's office, the Lab is the number one breed for biting.
We have a black Lab who will bite; whenever people come over, we have to tie him up to keep him from biting.
It's all in the training. Labs, as retrievers, do tend to have fairly soft mouths. Doesn't mean they wouldn't gladly take a bite of someone threatening one of *their* people.
I don't believe Dutch Shepherds have drop ears; IIRC they have prick ears just like Shepherds and Malinois. And are often brindled. Don't know if they can be black w/white chests (the others aren't supposed to have that). But it could be a "defective" dog, anyway. Entirely possible the dog just has bad weak ears that refuse to rise. Like my sister's GS.