The nativity certificate confirms that you are of Tennessee origin. The Tahsildar office usually provides this. The Anna University website provides the format.
The VAO (Village Administrative Officer), RI (Revenue Inspector), and Tahsildar must sign the nativity certificate. The VAO and RI are supposed to investigate your nativity's credibility. They need a few of the following items to complete the process.
Ration card for address verification
Active bank account in your name or in the name of your father.
If applicable, a property document
Other proofs may be required by the office. Someone from the office will come and personally verify.