The document discusses whether soap stock arising during the manufacture of refined edible oil and vanaspathi is a waste product eligible for exemption under Notification No. 89/95-C.E. or a by-product subject to excise duty. The appellant revenue department argued that soap stock is a by-product with commercial value and use, while the respondent manufacturer claimed it is a waste exempt from duty. The Commissioner (Appeals) rejected the department's appeal, finding the issue was res judicata based on a prior accepted order. The Tribunal examines the classification of soap stock and applicable case law.