Machine doubling. When you see the same doubling on the mint mark as on the date on coins previous to 1990 it is a 99.99% chance it's not a doubled die.
In machine doubling, a common situation is that only one lug or side is a tiny bit loose and moves. The other areas that don't can act as a pivot at difference points, causing greatest movement on the areas furthest from the pivot. I have seen some MMD that does affect most of one face, but it is less common. I have read that it was a common shortcut to reduce the lugs mechanically so they could be changed more rapidly, as heat generated during use striking coins, could expand the die and make it hard to remove.
