SPAC（Special Purpose Acquisition Company）直译为“特殊目的并购公司”，也称作“SPAC平台”，是美国资本市场特有的一种上市公司形式。其目的是为了并购一家优质的企业（目标公司），使其快速成为美国主板上市公司。

美国证监会将ADR定义为“一种由银行发行的、代表非美国公司公开发行证券的、可在美国金融市场交易的可流通金融工具”。

The basic idea of buying a shell to go public is for non listed companies to select and acquire a listed company, and then use the listing conditions of this listed company to inject the company's excellent assets into the listed company through methods such as rights issue, acquisition, and exchange.