As per Section 42(1), the details of inward supplies and input tax credit availed by the recipient and disclosed in FORM GSTR-2 have to be matched with the following: –
(a) Corresponding details of outward supply furnished by the supplier in his valid return for the same tax period or earlier tax period,
(b) Additional duty of customs paid under section 3 of the Customs Act in respect of imported goods, and Further, duplication of claims of input tax credit would also be noted. Also, the details of the GSTIN of the supplier, GSTIN of the recipient, invoice/debit note number, taxable value and the tax amount shall also be matched.
(ICAI FAQ PUBLICATIONS 06-09-2017 RETURNS : FAQ NO. 30)