Supplementary invoice

Hello,

My Client is a Builder (Private Limited), received a Supplementary Invoice from his contractor amounted to Rs.2, 96,640.00 /- as Service Tax on the invoices issue to company from April, 12 till date of getting service tax registration number by contractor i.e. 5.2.2013.

Now, my client is ready to pay only if they get Service tax input.

Please advice whether company to pay against Supplementary Invoice and get Input of ST or Not?

Thanks