Primary purchase evidence, accepted sales and unrejected books...

Primary purchase evidence, accepted sales and unrejected books may discharge the purchaser's burden unless the Revenue produces independent material showing sham supplies or return of consideration. A supplier's failure to substantiate its own procurement chain, alleged excess mining, or direct dispatch to customers does not alone justify disallowance. Where purchase evidence is deficient but sales, audited accounts and quantitative records are accepted, only the profit embedded in unverifiable purchases may be estimated, using the disclosed gross-profit ratio; complete disallowance would create artificial profits. A closing-stock balance in seized electronic records requires corroboration and cannot stand where incomplete consumption entries create a notional, improbable stock figure unsupported by physical stock or other defects.