Now here's the catch. If you're mark was established before a certain date, then it does not have to be registered, they advise it but does not have to be, it's grandfathered in, anything after that date (I don't recall the date, ill have to search) it has to be registered. The oldest mark I own, is dated from 1914, so it's grandfathered in, but they do advise you re-register it but you don't have to.
Here's the catch: you can run marked hogs here, but they have to be marked and barred on the spot
a neighbor cannot lawfully kill a marked hog, he must notify you if he's on his property, or he faces theft of livestock. You face civil liability for the damage done.
Livestock commission does not handle these cases, your local sheriff will and it's solely up to them as to what they want. We just had a case like this come up just a few months back and this was how the laws were read, and I spent countless hours on the phone with people trying to figure these laws out. They're pretty old fashioned and outta date.