Industrial Disputes Act, 1947
On receipt of an application from a Union for registration under section 9D and on payment of the fee prescribed, the Registrar shall, if, after holding such inquiry as he deems fit, he comes to the conclusion that the conditions requisite for registration specified in the said section are satisfied and that the Union is not otherwise disqualified for registration, enter the name of the Union in the appropriate register maintained under section 9C and issue a certificate of registration in such form as may be prescribed: Provided that- (i) where two or more Unions fulfilling the conditions necessary for registration under this Act apply for registration in respect of the same unit of an industry, the Union having the largest membership of employees employed in the unit of the industry shall be registered; and (ii) the Registrar shall not register any Union if he is satisfied that the application for its registration is not made bona fide in the interest of the workmen but is made in the interest of the employers to the prejudice of the interest of the workmen.