The process of marketing shares to, and gathering orders from, institutional investors in an equity market initial public offering (IPO). In an IPO, bookbuilding is usually carried out along with the investor roadshow, typically for a period of two weeks. This process is preceded by pre-marketing and the setting of a price range. In the case of de-coupled deals, bookbuilding is conducted shortly after the roadshow. Unlike in a fixed price IPO where a company determines the price of the share before the issue opens, in the bookbuilding process the issue price and the total amount of capital to be raised can be known only after the issue closes.

The bookbuilding process is also known as an open price offer or as a price discovery process.