Under section 8(1) of the Central Sales Tax Act 1956 an Interstate sale to a registered dealer can be made at the concessional rate of Central sales tax i.e. @2% existing at this time. But for claiming concessional rate of CST the seller needs to produce a declaration in the prescribed form duly filed and signed by the registered dealer in a prescribed form obtained from a prescribed authority.
The prescribed form for claiming concessional rate of CST u/s 8(1) is C form which is obtained by the purchaser from the sales tax authorities in his state and is given to the seller for the goods purchased at concessional rate. C form obtained from the purchaser needs to be furnished by the seller to the prescribed authority within 3 months from the end of the period to which the form relates as per rule 12(7) of the CST(R&T) Rules 1957. But the Prescribed authority may allow furnishing of C form after the said period if satisfied that the person concerned was prevented by sufficient cause from furnishing the C form within the said time.
The dealers in Punjab usually are asked to deposit the C forms along with their annual statement the last date for filling of which is 20th November every year or sometimes the date for submission of C forms is extended to 31st march or some other date. But sometimes the selling dealers are not able to file the C forms due to reason of non availability of C forms with the purchasing dealers or for some other reason. In such cases the C forms can be submitted even after the filling of annual statement or even at the appellate stage.
It has been held by the honorable Punjab & Haryana High court in R.S cotton Mills vs State of Punjab (Download Case Law) decided on 24-09-2008 relying upon the decision in Prestolite India Ltd vs The State of Haryana & others (1988) 70 STC 198 to the effect that C or D forms could be filled even after the filling of the return or at the appellate stage and same could be taken cognizance of.
Hence the C forms can be submitted even after the filling of annual statement i.e. at the time of assessment or afterwards and the same can be taken cognizance of since no loss is caused to the revenue by not filling the C forms along with annual statement.