These are the 50's the picture is the back of one and the front of the other. They are in Gem uncirculated from the cash vault at Wells Fargo.
I would venture to say that this appears to be more like a solvent smear than an ink smear...an ink smear would be much more pronounced with very dark streaks or blotches (in most cases). These type of smears are produced when heavily diluted ink-not solvent reaches the printing plate. It also appears to be a smaller type smear based on the images...which indicate that the reciprocal wipers did get the majority of the solvent away from the note..thus the light smear effect on a very small portion of the note. Just my view point...
Have to agree with RickieB here, definitely have the signs of a solvent smear. Let me show you mine and you can tell the difference between that and an ink smear: