Yobit just give opportunities to spammers. I am not saying that all participants are spammer but, most of them. They are very clever and they run new signature campaign by their exchange. They have not bothered to open new thread for their campaign. This is oppurtunity for them who are not accepted any btc signature due to spam. Seems Yobit just need rank. I don't think they are considering or maintain any quality of post. That's why most of board full by Yobit signature. However, I don't think there is any way to prevent them.