Depending on the state, it is possible that the taxes were not due until after you sold.  Most jurisdictions send tax notices in the late Fall with a due date of the first of the year.  

Since you sold the home prior to the beginning of the year, it is likely your mortgage company never paid them from your escrow.

Your settlement statement would have what your part of the taxes was.  You most likely paid them for your part of the year at closing.