1. Find where they live
2. Punch them in the throat
3. Take whatever I'll gotten profit they made
4. Blacklist them
5. Have a well earned drink.

Black list really :/ I doubt FA is going to enforce your T.o.S

I figured as much. > > blegh.

Or if someone publicly says they want to buy it, note the buyer know that the seller is violating the TOS. and post on the journal/submission?

I did, and they removed/hid my comment.

What I think PrettyKitty13 is suggesting is note anyone who makes an offer directly, avoiding the person who has violated your ToS so the buyer's are aware without any chance for the seller to hide your comments.

Yeah, thanks for the clarification. I meant that when I -did- post on their submission, they hid the comment. But hopefully it's all resolved now, as we came to an agreement and I refunded the design/took it back.

It's really hard to do much when they hide your comments T~T
Glad you managed to figure it out :3

As you specified that all rights belong to you as the artists, you may be within your grounds for some form of copyright shennanigans. Since that means you retain commercial rights and they are violating it, maybe taking it up with one of the FA staff would be best? I mean honestly, FA is pretty bad at dealing with the minutiae of copyright and generally only bother with really flagrant cases so I do not put much hope into it. But it is worth a shot I suppose.