No trade allowance permissible except as prescribed by rules or under bye-law.

No trade allowance other than an allowance prescribed by rules or provided under bye-laws, shall be made or received in a notified area by any person in any transaction in respect of notified agricultural produce, livestock or products of livestock and no civil court, shall, in any suit or proceeding arising out of any such transaction, have regard to any trade allowance not so prescribed or provided. Explanation.- In the case of notified agricultural produce and products of livestock, every deduction other than a deduction on account of deviation from sample, when the purchase is made by sample, or of deviation from standard, when the purchase is made by reference to a known standard or on account of difference between the actual weight of the sacking and the standard weight, shall be regarded as a trade allowance for the purposes of this section.