The answer is: Buying the entire bond or stock issue a company wants to sell at an agreed discount
Underwriting refers to a process when bank is raising capital from the investors on behalf of the companies who own the shares.
in order to gain profit from this, the bank need to buy the entire bond or stock at a discount during initial offering.
When the bank sell the bonds/stocks at the full price, the difference between selling price and the discounted purchase would be the profit that the bank acquire.
