Is it just the wording that's unique to each dropcatcher? For Snapnames they have this (no preorder):
"unsold 1 year 6 months ago at SnapNames (no preorder, asking $59, expired domain)"
Also for Namejet (still unsold with "highest of x preorders"):
"unsold 1 year 4 months ago at NameJet (highest of 2 preorders: $200, expired domain)"