In my opinion, it would not be something the abstractor would be liable for.  That is why the seller's sign the affidavit.  The underwriters realize that they are assuming certain risks in issuing title insurance and the affidavit allows them to go back on the seller. 

However, if you find it - definitely report it - as you did. I think that since they are required to be filed within 90 days you would notice them in most cases. 

It would be interesting to hear from an underwriting council with one of the major underwriters to see how they feel about it.

Best,
Robert A. Franco
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