In one sentence
The recorded document that discharges a mortgage or lien once the underlying obligation is satisfied.
The longer version
When a loan pays off, the lender records a release or satisfaction so the property's title reflects that the lien is gone. Missing or late releases cloud title and surface in the next transaction.
Tracking releases is classic post-closing and post-payoff work: unglamorous, easy to drop, and a source of title problems years later when nobody remembers.
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