Thanks everyone for the help. Sorry I've been out for a few days. In looking back through what paperwork I have from 11 years ago, I can't find anything that addresses paying back the severance pay. My DD214 calls it severance pay, not separation pay if there is a difference. Looks like I've got some research to do. I guess I wish they would have told me this when I came back in, and not waited until after I was retired. Negligence is no excuse though.