They can, but that's on them if they knowingly trade with someone who is marked
There is no technical restrictions preventing you from trading. It's just a database to warn people that they shouldn't be trading with you. If you...
It looks like SOP probably dropped the ball as Helen said she wanted them to handle it. She probably sent a message and they never got back to her,...
http://forums.steamrep.com/threads/howto-report-a-scammer-look-at-acceptable-format-before-posting.51/
This was a beta issue on Windows. Looks like its fixed now. Luckly I have a Mac too.
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