Defective planchet before it was coated in copper. Missing part of the planchet caused the reverse to lightly impress. At least that's my thoughts.
I'm going to go with "fractured die" Blakesly effect on reverse, sunken obverse for the broken section slightly so the die isn't striking with even pressure anymore, but die still intact for the time being. Yeah, a large precud in a way, but it's it's own thing. jcro57 had a dime like this on here a couple years back but the fractured part wasn't sunken. https://www.cointalk.com/threads/2007-roosevelt-dime-shattered-obverse-die-strike.337031/ they fracture somewhat like how this cent displays, it's not frequent but dies fracture/shatter from time to time. if you want, Cuds-on-coins website has a section for shattered dies on U.S. coins, it's not very thorough at all though but I have no idea how often it really occurs. the dime section is the most full of good examples from the 2000s. http://cuds-on-coins.com/shattered-dies-on-u-s-coins/ it's going to be 2010 to date, that's the best you're going to be able to do on it unless it's cataloged somewhere. think I'll go check ebay if there's any others. LOL
I've heard from another member your a bit of a legend around here. Is there a catch to this generous offer?
Not at all. Just send me $7 cash with the coin to ship it back. I also email you the HD photos I take. No tricks. I have a good reputation here and I keep my word. ~JC
There seem to be two light sources. (About K4 and K8 on the obverse.) This can mess with our interpretation of what we are seeing. It certainly looks like a large piece of the die is missing below the bowtie. It seems like the rest of the die chunk was still in place since many of the design elements are still visible (although some just barely). It makes me think that large area of the die broke loose but was still in place and tilted (which could account for the shoulder being visible but the last two digits of the date and the area towards the rim be missing.) Necoins, You'll really enjoy the expert photos. (Where did you find this coin, Virginia or eBay?)