PA Supreme Court: Unperfected Mechanic's Liens Can Be Stricken at Any Time

When a contractor files a mechanic’s lien against your property, it can feel like you are boxed in. The lien clouds your title, makes it difficult to sell or refinance, and puts you on the defensive. But the Pennsylvania Supreme Court’s decision in Terra Firma Builders, LLC v. King, 249 A.3d 976 (Pa. 2021), provides an important defense that homeowners should know about.

The Rule

Pennsylvania’s Mechanic’s Lien Law, 49 P.S. section 1501 et seq., imposes strict procedural requirements on contractors who file liens. One of those requirements is that the contractor must file an affidavit of service proving that the lien claim was properly served on the property owner. This is the “perfection” requirement under 49 P.S. section 1505.

In Terra Firma, the Supreme Court held that if a contractor fails to perfect the lien by filing the required affidavit of service, the property owner can challenge the lien at any time. There is no waiver. Even if the homeowner does not raise the objection until after trial has concluded, the court must strike the unperfected lien.

This is a significant departure from the general rule in litigation that defenses not raised promptly are waived. The Court treated the perfection requirement as jurisdictional, meaning the court lacks authority to enter judgment on an unperfected lien regardless of when the objection is raised.

Practical Impact for Homeowners

If a contractor has filed a mechanic’s lien against your property, one of the first things to check is whether the lien was properly perfected. If the contractor failed to file the affidavit of service, or filed it late, or served the lien claim improperly, the lien can be stricken.

This defense is available even if you did not raise it in your initial response to the lien action. Terra Firma makes clear that the objection can come at any stage.

Cost-Plus Contracts: An Additional Defense

More recently, in PW Campbell Contracting Co. v. Yetter, 339 A.3d 400 (Pa. Super. 2025), the Superior Court applied the strict compliance standard from Terra Firma to hold that a “cost-plus” contract is not a contract for an “agreed sum” under 49 P.S. section 1503(5). When work is performed under a cost-plus arrangement, the contractor must provide a detailed itemization of labor and materials and prices charged, as required by section 1503(6), rather than simply claiming a lump sum balance.

If the contractor claims a lump sum on a cost-plus contract without the required itemization, the lien is deficient and can be stricken.

The Bottom Line

Mechanic’s lien litigation in Pennsylvania is a technical area where the contractor’s failure to follow the rules can be your best defense. If you are a homeowner facing a lien claim, do not assume you have to pay. Have the lien reviewed to determine whether it was properly filed and perfected.

If you are a contractor, Terra Firma and Yetter are reminders that strict compliance with the Mechanic’s Lien Law is not optional. A lien that is not properly perfected is no lien at all, regardless of how meritorious the underlying claim.

Contact our office if you need help with a mechanic’s lien dispute.