Mechanic's liens are operation of State law, so it may vary from state to state. That said you can record a partial release of the lien.
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Because the debtor is only paying a portion of the lien debt, I would suggest you record a partial release of lien with the county recorder's office. If you are here in Marion County, you may be able to get a standard form to do so from the County Recorder's Office, in the City-County Building. If they do not have a form, they may be able to point you in the right direct, with regard to what should be recorded.
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