Tax exemption alignment: state GST notification amends eligible research beneficiaries, updates departmental reference, and provides retrospective effect. Revises the state GST rate notification to substitute the beneficiary description for serial 1 to include public funded research institutions, universities, specified institutes and regional engineering colleges (excluding hospitals), and replaces 'Department of Scientific and Research' with 'Department of Scientific and Industrial Research' for serials 1, 2 and 4. Inserts an Explanation aligning the State exemption with the Central Government customs exemption notification and declares the notification effective retrospectively from the stated effective date.