Dear R. Selvakumar,
The Trade Union Act, 1926, is the basic governing act, for the Trade Unions. (In the State of Maharashtra, they have a state legislation called as the Maharashtra Recognition of Trade Unions and Prevention of Unfiar Labour Practices Act).
The said act, does not bar a body of persons from forming a Trade Union, but only creates a minimum criteria for registration of a Trade Union.
In Industrial Law, a Recognised Union (normally the Union with highest membership) has the bargaining power.
Other Registered Unions, in the same Company, do have rights but is not recognised by the Company.
The minimum criteria, is created so that a Union which has the membership as prescribed are registered, and the other Unions, who do not fullfill the requirements, are not registered.
The Act does not bar them from forming a Union, but only creates a eligibility criteroa for being registered.
This infact helps the Industrial Harmony by not having several small unions, which in turn at the time of negotiations or bargaining, may not reach to a consensus, and would create an industrial dispute, putting the livelyhood of its members at stake.
Hence the Eligibility cannot be violative of the fundamental right guaranteed by the Consitution.
Thanks,
Ashish