Hi,
Normally, you have to provide an appointment letter, payslip, and relieving letter. The offer letter is not that important, and some companies nowadays ask for Form 16 issued by the employer for the last financial year. Even a copy is acceptable. In most companies, in their job application form, they ensure a declaration from the applicant, and beneath that, the applicant signs. The essence of the declaration is that the information provided by you is true to the best of your knowledge, and no false information has been given. In the appointment letter, there is a clause ensuring that if the information provided by you is found to be false, the management has every right to terminate the services. Hence, all information and documents provided by the applicant should be genuine. In this context, even if it is a copy, the management has every right to take action.
Most companies conduct background checks, and only after the completion and correctness of the check is every employee recruited.
Applicants should be very careful and cautious when providing documents and information in the above circumstances.
Regards,
Kameswarao