Straight from the horse's mouth:
- If you don't have a Federal Firearm License (FFL) you are considered an 'unlicensed dealer' by the ATF
- In a private sale firearms can be bought over the Internet, at flea markets/gun shows and informally from one individual to another; without paperwork or background check.
- An 'unlicensed' person may sell a firearm to an 'unlicensed' resident of their state; provided you don't believe the buyer is Mr. Stabby McRapington.
- An 'unlicensed' individual is prohibited from selling a firearm to a person who lives in another state.
- If you're uncomfortable about buying or selling with an 'unlicensed' person; utilize a current FFL to perform a background check.