Hi. About your concern. Nothing can happen in to you Steam if his trade was done with an impersonator.
First, his trade was done outside of Steam TOS:
STEAM TRADING POLICY.
They normally do not handle cases with Game Redeemable Keys obtained through a trade unless there are image copies provided in the ticket to show the chat conversation where the scam took place. In that case the ticket would lead to an investigation which would show what account the 5 Keys were sent to and would show it was not your account. So you should have nothing to worry about.
Unfortunately, since his trade was done outside STEAM TOS. He won't be able to get his keys back.
Hopefully, he will contact you and work things out seeing it was an impersonator.
Best of luck to you.
Ty for the response Genkisan. I'm amazed he still doesn't have a caution on his steamrep page.
If he hasn't been reported before, his SteamRep account would be clean. You actually can start a report yourself, seeing as he is still impersonating you. You should take a screen shot of his profile and file a report with his steamid32 and 64 number. With that you can also submit a ticket to Steam as well to file a complaint against him with the proof you have that he is impersonating you to do trade scams which will help to get him trade banned on Steam. As for reporting him here on SteamTrades, you would need to file a report through the SteamGifts network of SteamTrades: SteamGifts Support.
Information there should explain on how to report a user and get him suspended from SteamTrades.
Could you do me a massive favour Genkisan? Could you put a warning message in my rep page so when he links my rep page people know he is a scammer.
Scammer/Impersonator:
steamname: Catnip
steamID32: STEAM0:1:50473044
steamID64: http://steamcommunity.com/profiles/76561198061211817
customURL: [http://steamcommunity.com/id/catnlp](http://steamcommunity.com/id/catnlp_) (He has replaced the I with an L)
steamrep: http://steamrep.com/profiles/76561198061211817
link to his name history/people he has impersonated: http://steamcommunity.com/id/catnlp_/namehistory
My profile:
steamname: Catnip
steamID32: STEAM0:1:2094681
steamID64: http://steamcommunity.com/profiles/76561197964455091
customURL: [http://steamcommunity.com/id/catnip](http://steamcommunity.com/id/catnip_)
steamrep: http://steamrep.com/profiles/76561197964455091
DON'T TRADE WITH THIS GUY AND PLEASE ADD HIM TO YOUR BLOCKED USERS LIST
I have already received one negative feedback and I don't want other traders to suffer. You can see who he scammed by looking at the feedback on my profile, he is still in the friends list of the guy who got scammed. He is violating Steam's Online Conduct if anyone wants to report him.
He has impersonated other users: http://forums.steamrep.com/search/1932749/?q=76561198061211817&o=date
Google shows that he has also impersonated PaUx: http://www.steamtrades.com/trade/XfRHP/scammer-alert-impersonator
Turns out that PaUx knew he was impersonating me before I found out myself.
Update: I have spoken to three of his victims who have also reported him to steam. If he has scammed you or attempted to scam you please post evidence here: http://forums.steamrep.com/threads/76561198061211817.46144/.