It looks like machine doubling. The mintmark was handpunched into the die in those days so when you see the same "doubling" in the MM and the date it is highly unlikely to be a doubled die issue. Here are the two known on Variety Vista http://varietyvista.com/01b LC Doubled Dies Vol 2/DDO 1969-S.htm
The term is DOUBLED DIE as in the DIE itself is doubled. It happens because to transfer the design from the hard steel masters (hubs and dies) to the working die it takes two cycles of hardening the master / softening the die. If you don't get things PERFECTLY aligned for the two, you double the die. The signs of this are either "split serifs" (e.g. the fancy corners on letters show visible separation) or sometimes fattening (on sans serif design elements). "Mechanical doubling" or "Machine Doubling" happens on an individual strike when the planchet bounces a bit and the sign of that is a flat shelf as part of the "doubling" There are also doublings that occur when the dies are worn. Visit https://www.error-ref.com/ for much more information.
