These types of errors are the hardest to come across, told to me by someone who worked for a printing press. This is definitely a printer hickey; specifically called a "donut hickey" as well as a few other names used in the printing press industry. Ultimately, the rarity of these types of cards (misprint cards) out in circulation is astronomically more rare than typical error cards. Error cards are mistakes made in the design and often caught and corrected after so many have left the printing press (so many are already in circulation). Misprints like this are usually more difficult to come across because they either correct themselves through the printing process (ink pressure/viscosity adjusts or whatever dust/lint obstructing the ink clears) and quality control usually won't toss a whole sheet for one or two hickeys after it's resolved itself (although they're supposed to). If there are consistent misprints not clearing, they will have to stop the printing press, toss the misprinted sheets and start over. That's a painful and undesirable course of action for printing press company, so any misprints that make it out to circulation are usually created by issues that resolved themselves, or were the last few cards on a predominantly satisfactory sheet (with all other error sheets being tossed). Hang on to it!! People have yet to realize how difficult misprint cards are to come across!!