Start with the Ministry of Corporate Affairs. The MCA21 portal lets anyone search a company by name or Corporate Identity Number and view its master data: registration date, registered office, capital structure, directors, and filing status. A company that cannot be found there, or whose filings are years overdue, deserves caution.
Then cross-check the tax and procurement layers. The GST portal confirms whether a GSTIN is active and matches the legal name. The Central Public Procurement Portal, GeM, and state portals such as Rajasthan's SPPP show whether the firm has actually bid and won. Finally, ask for completion certificates from past clients and insist that payments go only to a bank account in the company's registered name.