The highest bidder is declared the winner of the bank auction. in case you win a public sale then you need to deposit 25% of the bid quantity within 24 hours consisting of EMD deposited with tender form. 
stability 75% of the bid quantity ought to be deposited within 15 to 30 days from the date of the bank public sale.

It is important to note that these rules may vary depending on the type of auction and the jurisdiction in which it is conducted.

You can check some of the leader auctions and identify the what are Legal and Regulations in Bank Auctions.

You can also check, How the Bank Auction Process works.