A public offering of securities that combines the features of both a primary seasoned offering and a secondary seasoned offering. In other words, it is partly primary and partly secondary, with both offerings being carried out at the same date. The offering combines primary and secondary shares. Before the expiration of the lockup period that prevents corporate management and other insiders from selling their holdings, the issuing company reappears in the market with a new sale of stock that consists of both new shares from the company and existing shares held by the insiders. Previously, insiders- including venture capitalists and other founding investors- would have had to wait at least six months to sell their holdings after an initial public offering (IPO). With combined offering, insiders can unload a portion of their holdings in as short a period as three months.

This offering is also known as a piggyback offering (PBO) or a hybrid offering.