Registration of a factory/ establishment with the Employees State Insurance Corporation is a statutory responsibility of the employer under Section 2-A of the Act read with Regulation 10-B. The employer, in respect of a factory/establishment to which the Act applies for the first time, is liable to furnish to the appropriate Regional Office within 15 days after the Act becomes applicable, a declaration of registration in form 01(Employers Registration Form). This is obligatory on the part of the Employer.