I got a call from a layer stating that it's against the law to file a lien on a residential property if a homeowner has paid the GC. We were hired as subcontractors from the GC, but the GC has not paid us and refuses to pay us. So we went ahead and placed a lien on the unpaid work we did (residential home). Am I breaking the law?
No, you are not "breaking the law," because filing a lien is not a criminal code where deviation warrants a penalty. However, if you were a subcontractor on a project (i.e. had no direct contract with the property owner), you must first file a Formal Notice which records that you made the owner aware of the debt prior to filing the actual lien. See https://www.foxrothschild.com/publications/refresher-on-the-pennsylvania-mechanics%E2%80%99-lien-law/.
The homeowner issuing payment to the GC for your contribution is NOT a valid justification to discharge your lien claim. If you are out of time to issue the Formal Notice, and then the lien, you may still have other stuatutory options for relief.