It really all depends. I wouldn't de-worm them unless you suspect something.

Interceptor prevents round, hook & whip worms so you don't need to worry about them if your dog is on interceptor. Revolution also protects against some too I think.

Tape worms are the safest type of worm. The dog has to eat an infected flea, mouse or feces to get them. And those you will usually see rice like segments around the dogs rear, possibly on the dogs bedding too in their feces.

If your dog is showing any symptoms, weight loss, diarrhea, or if you see them or if they have been around other animals that may have them I'd get a stool sample to the vets. Otherwise I wouldn't worry about it.

Nanook has had tapeworms maybe twice in his life. And all 3 were dewormed when I got them just to be sure. Kaige was still a pup so he needed to get treated. Almost every puppy is born with roundworms as roundworm larvae is tranmitted from the mother to the pup while still in the womb. Even if the mother doesn't have roundworms. A female dog is ablt to harbor roundworms in her tissue often making them immune to dewormings. Nanook & Raustyk were shelter dogs with unkown history.