A natural person refers to a human being, so it's $5 million for natural persons and $25 million for institutions.

一个自然人指一个人,一个自然人需要500万美元,而一个机构则需要2500万美元

耶鲁公开课 - 金融市场课程节选

A qualified purchaser has to have at least $5 million dollars or, if it's an institution, at least $25 million -that is a natural person.

一个合格购买者至少持有500万美元,如果是机构则需要至少2500万美元,...这里指的是自然人

耶鲁公开课 - 金融市场课程节选