Once a mortgage always a mortgage.

Explanation

(English-origin maxim.) A transaction that is in substance a mortgage cannot be converted into an absolute conveyance by any device of the parties — equity will always permit the mortgagor to redeem, regardless of the form of the instrument.

Where this applies

• A borrower deeds his home to a lender with an agreement that the borrower can repurchase it after paying the debt, and the court treats the arrangement as a mortgage with a right of redemption, regardless of what the parties called it.
• A car dealer structures a sale-leaseback to avoid foreclosure protections, but the court looks through the form and holds that the transaction is in substance a mortgage, preserving the buyer's right to redeem.
• A pawnbroker claims that a customer 'sold' her ring outright, but the agreement allows the customer to buy it back within 90 days — the court treats it as a pledge with redemption rights because substance controls over form.