Input tax credit restrictions govern concessional state tax on specified bricks, blocks and tiles under the Assam GST notification. Concessional state tax at 3% is prescribed for specified intra-state supplies of bricks, blocks and tiles, including fly ash bricks, fossil meal bricks, building bricks and earthen or roofing tiles, subject to conditions that no input tax credit is taken on goods or services used exclusively for such supplies and that proportionate credit is reversed where inputs or services are used partly for such supplies and partly for other eligible supplies.