Dew claws on hind legs.

Question
I've had a yellow labrador retriever female for about 5 months.  I just recently bought a black labrador retriever male pup from people I heard about online.  They own many labs, more than countable.   But what makes me curious is that my Black lab has hind leg dew claws, and my yellow lab does not.  People online are saying labradors are not supposed to have hind dew claws.  But I wanted to ask you, just incase.  I also know that they've proven with their male yellow labrador retriever that the pup is AKC.  But they also said that a stray Great Pyrenees has recently breeded with one of their female labradors.  I also know that Great Pyrenees dogs are known to have hind dew claws.  My question here is.. Is it possible that an AKC labrador retriever has Hind Dew claws?  And if not, am I capable of suing the people who sold the pup to me for false advertisement?

Answer
I can say Labs usually don't have back dew claws.  All sorts of things crop up now and then.  Perhaps too much for you to win a suit.  I am on much shakier ground on the legal issues.  Even if you forced them to do DNA testing and prove the alleged parents were indeed the parents of your dog, any misbreeding could go back further.