CLASSIC Negative Feedback!

[Deertick]

•We'll count Detailed Seller Ratings (DSRs) of 1 and 2 only if they come from two or more buyers within any given evaluation period.
•If a buyer is warned or suspended for buyer abuse, any Feedback, DSRs or Buyer Protection cases they have opened won’t affect your status as a seller.
•Feedback and DSRs left by buyers who consistently leave much lower than average scores will be hidden and won’t affect your status as a seller.
•If you receive Feedback that violates our Feedback policies, you can contact eBay to report and request Feedback removal.

And

However, buyers can leave Feedback in these situations:
•Before Unpaid Item Assistant opens the case
•If they pay after the case is opened
•If they successfully appeal after the case is closed (any previous Feedback left will be reinstated)
•If an unpaid item wasn't recorded on their account after the case closed