(a) A leverage transaction merchant must use the same bid price at any particular point in time to purchase a leverage contract from a leverage customer (initiation of a short transaction) and to repurchase a leverage contract from a leverage customer (close-out of a long transaction), and a leverage transaction merchant must use the same ask price at any particular point in time to sell a leverage contract to a leverage customer (initiation of a long transaction) and to resell a leverage contract to a leverage customer (close-out of a short transaction), with respect to contracts involving the same leverage commodity.

(b) A leverage transaction merchant must apply a carrying charge rate on a short leverage contract that is within one percent per annum of the carrying charge rate that it applies to a long leverage contract. In the case of a short leverage contract, the leverage customer must be credited with carrying charges computed on the total initial value of the contract, using the bid price when the contract was executed, plus any margin deposits made by the leverage customer in connection with the contract, and the same carrying charge rate must be applied to the total initial value of the contract and to the margin deposits. In the case of a long leverage contract, the leverage customer must be assessed carrying charges only on the unpaid balance of the contract, which is the total initial value of the contract, using the ask price when the contract was executed, minus any margin deposits made in connection with the contract: Provided, however, That in the case of a long leverage contract, interest on unpaid carrying charges may be assessed at the same rate as the interest rate component of the carrying charges and, if such an assessment were made and if the leverage transaction merchant offers short leverage contracts, payment of interest on carrying charges that have been credited to the leverage customer's account and not withdrawn must be made at the same rate as the interest rate component of the carrying charges.