Accepted Report: 76561198028307130 (Derp Vader)(Impersonator)

Can you please click on that "Derp Vader" link in your inventory history and copy/paste the profile URL that it goes to? I suspect you may have traded to an imposter.

Yeah, it looks like you got scammed by an imposter. Who is already marked on SteamRep: http://www.steamrep.com/index.php?id=76561198018123225

In the future, always grab the URL of whoever you are talking to and run it through SteamRep.com. It will tell you right away if you're talking to a known imposter. He probably made his profile look just like the real Derp Vader, but it can only be seen by people who friend him (since his profile is friends' only).

I'll add this note to the list of his scams. Thanks for reporting it, and be careful out there.

Hopefully you reported the imposter: http://steamcommunity.com/id/darpvader and not the other fellow. If so, please correct your Steam Support ticket with the real thief.