@garyis2000 @shizzlemetimbers @smpratte For the white imprint on the back, it doesn’t happen with just Energies. I’ve got a Pikachu with a white imprint on the back as well, but it’s positioned in the middle as imprint from a regular Pokémon card, whereas the stamps for Energies like you have are at the top (and it’s also possible to have it near the bottom from a Trainer imprint).
Instead of a white stamp, it is also possible to have a black imprint. I personally see those more often. For the black imprint it’s simply the 1st edition ink that wasn’t properly dried yet when the uncut sheets were stacked on top of each other (which might also be the cause for some of the grey stamps at the front).
I’m still not sure how these white stamps are formed however… At first I thought the ink might have acted kinda like glue, ripping the front of the card with the 1st edition stamp, causing the card residue (the white) to remain. But I don’t see any evidence of this on the white imprinted Pikachu I have. If anyone has a more plausible cause for these white imprints on the back I’d love to hear it.
I also mention both in my 1st edition stamps variations article (as White Back Imprinted stamp and Black Back Imprinted stamps respectively). The white back stamp on my Pikachu isn’t nearly as clear as your cards, though. (If anyone has a Pikachu with white back imprint that’s clearer, I’d love to buy it. 
)
Greetz,
Quuador