im pretty sure they arnt they come with all paper work and which car it came out of. I was told they come out of wrecked or damaged cars bought by this company and they do a check on the engine when they pull it out of the car, fix whatever was damaged (if there is any damage to the engine), put it through tests and such to make sure it is 100% in working condition. Plus there is a warranty you can get for it. This is why im going up there to check out the scene make sure everything legal before i just buy it and have them ship it to my house.