7 U.S. Code § 936a - Prepayment of loans
No sums in addition to the payment of the outstanding principal balance due on the loan may be charged as the result of such prepayment against the borrower, the fund, or the Secretary.
Any guarantee of a loan prepaid under this section shall be fully assignable under the provisions of section 936 of this title and transferable. However, the Secretary may require that any such guarantee, if transfered  or assigned, be transferred or assigned to a loan or security that, if sold, will be grouped with nonguaranteed loans or securities and sold in a manner to ensure that such sale will not unreasonably compete with the marketing of obligations of the United States.
 So in original. Probably should be “transferred”.
Public Law 99–349, referred to in subsec. (d)(1), is Pub. L. 99–349, July 2, 1986, 100 Stat. 710, known as the Urgent Supplemental Appropriations Act, 1986. Provisions of title I of Pub. L. 99–349 relating to prepayment of loans were set out as a note under section 936 of this title and were repealed by Pub. L. 99–509, title I, § 1011(b), Oct. 21, 1986, 100 Stat. 1876. For complete classification of this Act to the Code, see Tables.
1994—Pub. L. 103–354 substituted “Secretary” for “Rural Electrification Administration” in subsec. (b) and “Secretary” for “Administrator” wherever appearing in subsecs. (d) and (e).