Exactly as Tiny said..He is just bring impatient and letting you know he's not really happy about standing still..My gelding started doing it for whatever reason..while standing bring ridden, standing tied, and waiting on his feed..I had to quickly fix it and not allow it to get worse. If he did it when riding I would make an 'ah, no" noise sort of loudly, not screaming but enough to get his attention and "heel" him in the shoulder. He would stop and then start again..So, that was a slow process but eventually he stopped doing it while I was riding. Standing tied was a whole different ball game. I wasn't standing in reach of him at all times and he would paw..I yell the same "ah, NO!" And he would stop and give me this "oh crap" look..if he wouldn't stop pawing I would throw a brush or whatever small object was close (I don't reccommend this for every horse but it got his attention..and he's a spoiled brat) so he would get hit with a rock or something and yelled at..eventually I didn't have to throw things anymore and he knew if he heard "Ah NOOO!" He was in trouble and I got the "oh crap!" Look from him...pawing waiting on his feed still is a habit..I can't stop that for the life of me..yelling, throwing things, chasing him..nothing works.. he will just trot off and do it again with a smarta** look on his face and I can't just hear him saying "Ah ha! Now what woman?!"... So it's a habit you can break, it just takes time, patience, and getting creative to find what works for you..
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