Securities underwriting refers to the process by which investment banks raise investment capital from investors on behalf of corporations and governments that are issuing securities (both equity and debt capital). The services of an underwriter are typically used during a public offering in a primary market.
My understanding is sometimes the underwriter buys all the shares for a certain price then makes them available to retail clients for a higher price. Or sometimes they just get paid a fee for their services. Since this in not an IPO but rather a new offering of an existing stock, I am not sure how it will unfold. The bottom line is we get promotion of POET stock.