Sales tax exemption tied to manufacturing can be withdrawn after statutory amendment removes tea blending from the definition of manufacture.

Sales tax exemption under section 39 of the West Bengal Sales Tax Act, 1994 depended on carrying on a manufacturing activity within section 2(17). Once the statutory definition was amended to omit blending of tea from "manufacture," tea blending no longer satisfied the condition for continued exemption. The eligibility certificate created only an existing statutory benefit, not a vested right immune from legislative change, so the exemption could be prospectively withdrawn by amendment. Authorities based on promissory estoppel and subordinate legislation were distinguished. The constitutional challenge was not examined.

---

---

Issues: Whether the petitioners could continue to claim sales tax exemption under section 39 of the West Bengal Sales Tax Act, 1994 after the statutory definition of "manufacture" in section 2(17) was amended to omit blending of tea, on the footing that the eligibility certificate created an inviolable vested right.

Analysis: The exemption under section 39 was linked to carrying on a manufacturing activity within the meaning of section 2(17). Before the amendment, blending of tea was treated as manufacture only because of the inclusive definition. After the Legislature omitted that inclusion, tea blending no longer answered the statutory description of manufacture and therefore could not continue to attract the exemption. The right enjoyed by the petitioners was held to be only an existing statutory benefit, not a vested right immune from legislative change. The Court distinguished cases based on promissory estoppel and subordinate legislation, and held that legislative amendment could prospectively curtail the continuing benefit. The constitutional challenge was not examined.

Conclusion: The petitioners were not entitled to continue the tax exemption after the amendment, and the claim of an inviolable vested right was rejected.

---