The Supreme Court of India has held that In matters relating to service jurisprudence, time and again it has been held that it is not essential to implead each and every one who could be affected but if a section of such affected employees is impleaded then the interest of all is represented and protected. In view of the above, it is well settled that impleadment of a few of the affected employees would be sufficient compliance of the principle of joinder of parties and they could defend the interest of all affected persons in their representative capacity. Non-joining of all the parties cannot be held to be fatal.
Copy of the judgment is attached