lien theory
lien theory. The idea that a mortgage resembles a lien, so that the mortgagee acquires only a lien on the property and the mortgagor retains both legal and equitable title unless a valid foreclosure occurs. • Most American states — commonly called lien states, lien jurisdictions, or lien-theory jurisdictions — have adopted this theory. Cf. TITLE THEORY. [Cases: Mortgages 136. C.J.S. Mortgages § 183.]