Floating-rig services are classifiable as Supply of Tangible...

Floating-rig services are classifiable as Supply of Tangible Goods Service, taxable only from 16 May 2008, rather than Mining Service. Service tax collected under the erroneous classification and borne by the service recipient lacked legal authority under Article 265, supporting refund even though the service provider had not challenged its assessment. Statutory refund limitation did not justify retention where payment arose from a mistake of law caused by misclassification. Certificates establishing that the recipient bore the tax burden supported the finding that refund would not result in unjust enrichment. Appellate authorities and the Tribunal could correct the classification error and grant refund without requiring a civil suit or writ petition.