This article is from the eBay FAQ, by William B. Shaw email@example.com with numerous contributions by others.
The short answer - you can't. There appears to be only three ways to get a
negative feedback erased from your record. First, if you can show that the
feedback YOU left was for the wrong user by referring the eBay
representative to another user where you left identical feedback. Secondly,
you can apply to Square Trade (http://www.squaretrade.com), pay them $15 to
mediate and IF the other party cooperates and agrees, the feedback can be
removed. Finally, obtain a court order. Check with your attorney to
determine costs and the timeframe associated with this type of action.
EBay's policy on this can be found on their Feedback Basics page located at
If you receive an unjust negative feedback, remain calm. The character
portrayed in your response is more important than the feedback itself. Leave
a factual, professional response and forget about it. Your trading partners
will most likely understand and not hold it against you unless they see a
pattern of negatives.