In my experience the ad back cards don't receive a value premium but they are more scarce. The 1927 copyright version of Babe Ruth does command a premium of 3x-5x....from my experience. I paid way more for my 1927 but it's because I was duking it out with another collector and it was an abberation (imo)...which was really good for the consignor and auctioneer but not so much for me
edited to add that on further thought the ad back will probably command a small premium. I would pay a small premium
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