7 U.S. Code § 8772 - Dairy forward pricing program
The Secretary shall establish a program under which milk producers and cooperative associations of producers are authorized to voluntarily enter into forward price contracts with milk handlers.
To assist milk handlers in complying with paragraph (1)(A) without having to segregate or otherwise individually track the source and disposition of milk, a milk handler may allocate milk receipts from producers, cooperatives, and other sources that are not subject to a forward contract to satisfy the obligations of the handler with regard to Class I milk usage.
A milk handler may not require participation in a forward pricing contract as a condition of the handler receiving milk from a producer or cooperative association of producers.
A producer or cooperative association described in paragraph (1) may continue to have their  milk priced in accordance with the minimum payment provisions of the Federal milk marketing order.
No forward price contract may be entered into under the program established under this section after September 30, 2018.
 So in original. Probably should be “its”.
The authorities provided by each provision of, and each amendment made by, Pub. L. 110–246, as in effect on Sept. 30, 2012, to continue, and the Secretary of Agriculture to carry out the authorities, until the later of Sept. 30, 2013, or the date specified in the provision of, or amendment made by, Pub. L. 110–246, see section 701(a) of Pub. L. 112–240, set out in a 1-Year Extension of Agricultural Programs note under section 8701 of this title.