To give notice that a loan was given on a cooperative apartment, a UCC-1 Financing Statement is typically filed. This is a legal form that a lender files to provide notice that it has a security interest in the collateral of the borrower. In the case of a cooperative apartment, the cooperative corporation's shares and proprietary lease would be considered the collateral securing the loan. By filing a UCC-1 Financing Statement, the lender asserts its interest in the cooperative shares and lease, which provides notice to other potential creditors or buyers of the cooperative apartment. This filing helps establish the lender's priority in case of default or other legal proceedings involving the cooperative apartment.