Job work as a treated supply: principals must observe return time limits, documentation, and tax consequences for nonreturn. Job work is a form of supply under GST where a principal may send inputs and capital goods to a job worker without payment of tax subject to time limits for return (one year for inputs; three years for capital goods), failing which the transfer is deemed a supply by the principal and tax with interest is payable. Principals must maintain accounts, issue challans and file FORM GST ITC-04; e-way bills are required for inter-state movements and job workers must register if turnover exceeds the threshold.