Mahabir Vegetable Oils Pvt. Ltd. & Anr vs State Of Haryana & Ors

The Supreme Court addressed the applicability of promissory estoppel in the context of the Haryana General Sales Tax Act, 1973, particularly Section 64 and its sub-sections. The Court held that the retrospective effect of rules made under the Act, as per the amended sub-section (2A), does not adversely affect the rights of individuals who are entitled to benefits under the industrial policy. The judgment clarified that the solvent extraction plants were eligible for sales tax exemptions as they were not included in the negative list, thereby upholding the rights of the appellants.