https://www.comc.com/Cards/Baseball/...ure,sr,ot,i100
A seller or two have also been selling blank back proofs with no signature on them through COMC.
![](https://img.comc.com/i/Baseball/1982/Topps---Base---Blank-Back-Without-Signature/DAMU/Dale-Murphy.jpg?id=f3c946fc-29e7-4f96-b573-2936ce0f3e98&size=zoom)
You can see on this Dale Murphy blank back that the black line around the photo is present, while the signature is missing. Not a true blackless card, but another interesting variation nonetheless.
I think COMC is mis-characterizing the In Action cards (and I've reported it to them) because those cards don't regularly come with the signature. Those should just be listed as blank backs.