Unjust enrichment amendment could not retrospectively defeat a refund already sanctioned and paid before the statutory change.

An amended unjust enrichment rule could not be used to defeat a refund claim where the refund had already been sanctioned and paid before the Central Excises & Customs Laws (Amendment) Act, 1991 came into force. On those facts, the amendment had no retrospective operation over a completed refund, so the refund could not be reopened on the ground of unjust enrichment. The Revenue's challenge therefore failed.

---

---

Issues: Whether the amended unjust enrichment principle could be applied to defeat a refund claim where the refund had already been sanctioned and paid before the amendment came into force.

Analysis: The refund had been sanctioned and the amount had actually been paid before the Central Excises & Customs Laws (Amendment) Act, 1991 came into force. On those facts, there was no legal basis to invoke the amendment retrospectively to deny the refund on the ground of unjust enrichment.

Conclusion: The amendment could not be applied to the completed refund, and the Revenue's challenge failed.

---