Dear Armaan,
In addition to what is stated by other fellow members, I would like to state that when you engage any contractor who is deploying 20 or more workmen, the Principal Employer has to enter into a legal contract with the Contractor as well as issue Form V to the Contractor to obtain a license under the CL(R&A) Act. Since you are based in Mumbai, I believe the premises are in Maharashtra. The labor authorities are very strict and vigilant about the CLRAA issues. Also, retain copies of the licenses obtained by the Contractor for your records and reference.
The Registration and License is valid during a calendar year, i.e., Jan to Dec, and before the expiry of the annual Registration/License, a system has to be kept in place to renew these contracts at least 60 days in advance, i.e., before the end of October. Similarly, if there is any change in the number of contract labor registered or a change in the contractor, ensure that immediate intimation is filed with the Competent Labor Authority. Hope this is sufficient to have an overview of the registration/license processes. In case you want more info, please write to me at abhirutu@rediffmail.com. Regards and wish you all the best.