Dear Sir/Ma'am,
CIN-Mandatory
As per Section 12 of the Company Act notified from 1st April, 2014, every company is mandatorily required to mention its Corporate Identification Number (CIN) along with the name and address of registered office on letterheads, invoices, notices and on all official correspondence and publications. Additionally, contact details, email and website address, if any, must be incorporated in such documents mentioned from April 1, 2014.
In case of any failure to quote the CIN number, penalty of Rs 1,000 per day shall be imposed on the defaulting company and on every officer in default for every day during which the default continues. However, maximum penalty imposable shall not exceed Rs 100,000.