What is an Offer for Sale of Shares? What is an Offer for Sale of Shares? An Offer for Sale (OFS) is a method used by companies to sell existing shares to the public. Kiran Shroff / Tuesday, February 4, 2025 / Article rating: 4.3 Unlike an Initial Public Offering (IPO) or Follow-on Public Offering (FPO), which involve issuing new shares to raise capital, an OFS is a sale of shares that are already in circulation.