Previous homeowner had work done on roof in September. We closed October 19th. How are responsible for this?

Maryland law gives a party who improves real estate the right to file a mechanic's lien against the property to collect payment. The title search in connection with the sale would not have caught if closing occurred prior to the lien filing. However, to establish a lien in Maryland the roof contractor would need to file a petition to establish a lien and then there is an evidentiary hearing for the court to determine if the contractor has a factual and legal basi to move forward with the action (the court allowing the lien to be established doesn't mean the contractor wins, only that the contractor can proceed with the suit to enforce the lien, which moves through the court system the same way a breach of contract would move through the system). I would check the documents executed between seller and buyer to see if any representations or warranties exist upon Seller to defend, protect, and hold you harmless from claims arising out of pre-closing actions of the Seller. At the very least, I would send the Seller a demand letter directing that this matter be resolved immediately. See also Levelset article at https://www.levelset.com/blog/what-if-your-mechanics-lien-is-filed-after-the-owner-sells-the-property/ 

This is extremeley fact dependent so it's hard to help without knowing more specific circumstances. I'm also unclear as to whether you recieved a Notice of a Mechanic's Lien or a Petition to Enforce (or Establish) a Lien or a final judgment. The Seller may be responsible for this though.

Previous owner had work done on the roof in September. I closed on the home October 19th. The contrator was paid in full by previous owner of the home. The contractor did not pay the sub for material. we received a lien with previous owner and our name on the lien. Should be worried and also this wasn't in our closing documents 

In addition to prior responses, note that in MD there is no right to lien for improvements to an existing home unless the total value of the improvements is at least 15% of its value before it is subject to a mechanic’s lien in Maryland. The 15% is the total value of all improvements performed by the GC or on behalf of the GC's subcontractors, not just the value of work performed by the subcontractor seeking payment). See Maryland Real Property Code Section 9-102(a). Also, if the general contractor was paid in full prior to the time the original owner or you received a notice of intent to lien, which is a condition precedent to a subcontractor's right to establish a lien, then if you can produce evidence of payment in full to the GC prior to the time the sub sent notice of intent, then the sub's petition to establish a lien, if and when filed, would be denied. Winkler Construction Co. v. Jerome, 355 Md. 231, 734 A.2d 212 (1999); Ridge Sheet Metal Co. v. Morrell, 69 Md. App. 364, 517 A.2d 1133 (1986).

Unfortunately, document review would be needed for something like this. Without seeing the actual closing documents and papers you recieved from the contractor, there is not much help an attorney could provide you right now. Regardless of whether you choose to link up with me or another attorney, I recommend getting some kind of representation for this matter and contacting an attorney directly rather than on a public forum so the attorney may be able to provide you with specific legal advice.

Thanks for information