According to Texas Parks and Wildlife Code Section 1.101(4) and Texas Agriculture Code 161.001(a) [4], feral hogs are classified as exotic livestock and are property of the landowner whose land they are upon at any given time. Therefore, if you're on your own property no need in marking them if you just want them to be yours.
there for if the hog moves onto public land or anybody elses property, then the hog is free for the taking, no matter who has marked it right? if i catch or shoot a hog with a marking on it, then the previous catcher owner should have takin it with him/her in the first place