The Offer for Sale (OFS) is a simple way for large shareholders, like company founders or major investors, to sell some of their shares to the public. It’s done through the stock exchange to make the process fair and transparent. Originally, only founders or promoters of a company could use OFS to sell shares and meet the rule requiring at least 25% public ownership. Now, others who own at least 10% of a company's shares can also sell through OFS if they want to reduce their holdings.