Seller, but the Onlooker gets a 10 or 20 gold reward for reporting it, and it's a nice thing to do on the Onlooker's part. I've been the Onlooker several times, and I like knowing that the Buyer got to be notified of their pattern being uploaded because of me, and that the Seller got to be rewarded for their generosity.
Of course, the seller gets this reward. The one who uploaded the pattern gets the reward. But there is such a system that you need to leave a comment in the Bounty topic to get this reward. Therefore, the seller receives a PM letter from the moderator so that he does this. Until you leave a comment, the reward is not paid. But from my own experience .... if the Bounty is very old and several years old, then the process of receiving the reward is often delayed. I recently responded to an old Bounty. Then they credited me with the reward only after an onlooker was found who notified it.
But sometimes the title of the bounty is not very clear or has the wrong information so the moderator will not find it.
Thanks it can happen that a member see this and he /she can report it in the link above.
He /she will get a little reward for reporting it.
The big reward of the bounty will go to the member who posted the pattern.