I asked a guy who was selling boat loads of sporting logos if he had a license. He said in over 20 years he never had a license and the first order is a cease and desist so he wasn’t worried. I wanted to strangle him.
I did a little searching and found these guidelines.
It also contains some links and email addresses for the specific branches. I already sent an email out to the Army asking for information and will share that when I get it.