Section 12(d) in The Employees' State Insurance (General) Regulations, 1950
(d)Upon receipt of the completed Employer's Registration Form, the appropriate Regional Office shall, if satisfied that the factory or the establishment is one to which the Act applies, allot to it an Employer's Code Number (unless the factory or the establishment has already been allotted an Employer's Code Number) and shall inform the employer of that number.
