Gatemark top, gatemark bottom?

Here's one for you c.i. technology experts. Would you think it was matching, original parts, if you saw a footed No. 6 camp DO, and you saw gate mark on the bottom of the pot, but no gate mark on the accompanying lid? I saw this at a junk shop this weekend, and figured it had to be an odd mating. If the technology available at the time of manufacture for one part was to create gatemarks, then I would assume the same technology would be employed to manufacture the lid, right? I looked closely, and I saw no signs in the surface there had ever been one on the lid, and just ground off. The quality of the pieces was high, and a nice fit, too. 
