This form is to be issued by the selling dealer who makes the first inter-State sale during movement of goods from one state to another to enable his purchaser to claim the benefit of exemption from C.S.T. on the second inter-State sale effected by him during the movement of goods. This form is required to be obtained from the Sales Tax Officer.
suppose: X situated in Delhi purchased goods from Y in Punjab .Y booked the material on transport and send GR/RR(goods receipt note issued by transporter) to X. X instead of receiving material from transport himself sold the material to Z in Delhi (same state) by endorsing RR/GR in the name of Z.Z takes the delivery from the transporter .
In this case sale from Y to X is covered under CST and X to Z is also covered Under CST as sale in transit.
To complete the transaction X will issue C form to Y , Y will issue E-1 form to X Z will issue C form to X
In the above case even X & Z both are situated in Delhi but the sale transaction is covered under "sale in transit" clause of CST act so CST will be applicable and vat is not be charged.