Rule 28 of CGST Rules: This rule deals with the value of supply between distinct or related persons, stating the value can be open market value, value of like kind and quality, or determined by rules 30 or 31. The second proviso to Rule 28 states that if the recipient is eligible for full ITC, the value declared in the invoice shall be deemed the open market value.
Circular No. 199/11/2023-GST:
Clarifies taxability of services provided between offices of the same organization in different states.
If full ITC is available and no tax invoice is issued, the value may be deemed as Nil and considered open market value.