A construction company having its HO in WB with registration under WB VAT Act, and also registered with Assam VAT Act. In the year 05-06 the company got a contract from NF Railway, Maligaon, Assam to build a bridge at Assam. In this connection the company purchased steel from outside of bengal for the year 05-06 & 06-07 and fabricated the bridge in west bengal. After fabricated the bridge the same was sent to Assam by using Assam way bill. NF Railway, Assam deducted the VAT from us when they paid our bill in several times and issue Form 29 under Assam VAT Act. In the year 08-09 we issue the Form C to the suppliers against the purchases made for the year 05-06 & 06-07. In the current year while I visit the CTO for assessment for the year 08-09, the officer claim VAT against the issued C form (issued on 08-09) amount which was purchased for the year 05-06 & 06-07. Pls. advice me can CTO claim VAT against the above matter. Pls. guide & help me how I safe the VAT liability.