Companies that have pursued SPAC deals include iBuyers Opendoor and Offerpad, even as additional SPACs are waiting in the wings and looking for future potential mergers. Such firms, which are also called blank-check companies, allow would-be public corporations to begin trading shares without jumping through the usual hoops that come with a conventional initial public offering (IPO). And for that reason they've become increasingly popular both in real estate and in the broader market.