Okla. Stat. tit. 46 § 4.1
The provisions of this section shall only apply to mortgages securing an extension of credit made primarily for an agricultural purpose as defined in paragraph 4 of Section 1-301 of Title 14A of the Oklahoma Statutes where the mortgagor is either a natural person or a farm or ranching business corporation as defined in Section 951 of Title 18 of the Oklahoma Statutes. Every instrument substantially the same as the above shall be deemed a good and valid mortgage, with all contracts and covenants essential to protect the rights of the holder thereof; but any further lawful contract embodied therein shall be binding upon the parties thereto; and when the words, "and waive the appraisement" are written or printed therein, the premises mortgaged must be sold without appraisement, in case of foreclosure and sale thereunder, and in such case no order for such sale shall issue for six (6) months after the date of judgment; likewise nothing in this title or in Sections 10 and 11 of Title 42 of the Oklahoma Statutes shall be construed to prevent a mortgagor, in a mortgage transaction not involving a consumer loan as defined in Section 3-104 of Title 14A of the Oklahoma Statutes, from mortgaging and assigning the rents and profits from the mortgaged real property as additional security for the debts secured by the mortgage, where such assignment (i) is made contemporaneously with the execution of the mortgage, either as a provision therein or by separate instrument, and (ii) covers a lease or leases then existing or thereafter executed, including renewals or extension thereof or substitutes therefor, which cover all or any part of the mortgaged real property, and (iii) is an assignment not conditioned upon a future default by the mortgagor, and (iv) provides for the immediate collection by the mortgagee, or its successors, assigns or agents, of the rents and profits so assigned as the same become due. Any mortgagee taking an assignment of rents and profits as described above shall have the obligation to account and pay to the mortgagor regarding any rents and profits actually collected pursuant to such assignment, which are not applied on the indebtedness owing to the mortgagee; however, the mortgagee shall not be deemed to have other fiduciary obligations to the mortgagor resulting from such assignment or be deemed to be in possession of the mortgaged real property, unless the mortgagee also enters into continued physical possession of the mortgaged real property and exercises exclusive operating control of the mortgaged real property.
Okla. Stat. tit. 46, § 4.1