I'm beginning this thread to provide a list of guilds who will guarantee the trades of their members as a self-policing measure to the seemingly recurring problem of trade scams. This isn't intended as a discussion of the merits of the idea or whose scamming. Simply a list of guilds who will 100% stand behind the trades, including lootspots and gem-gift trades offered by their members, posted or otherwise. Kind of an "Underwriters Laboratory seal of approval" of trading with people who belong to the guilds offering the guarantee. If your guild is willing to stand behind trades offered by your members in the event of an intentional/unintentional unfair trading event please post your guild's name and the name of the player(s) (preferably an officer) who should be contacted in the event that a player believes that they have been scammed or cheated. Names of alleged offenders or details of the bad trade or scam shouldn't be disclosed here, but rather only privately with the guild contact.
If you believe that you've been scammed or cheated by a member of a participating guild, contact the individual(s) named in that guild's post in this thread. Screen caps of chat logs, Trade Office offers, confirmation of the problem by other players, etc. will be helpful.