The trading of crude oil funds was suspended because QDII(QDII quota is qualified domestic investors) is not enough. Due to the COVID-19 epidemic and Saudi Arabia's substantial increase in crude oil production, crude oil prices have fallen sharply, which makes many investors want to participate in the bargain-hunting of crude oil prices. With the increase of purchase volume, crude oil funds will face the problem of insufficient quota.

China has a special QDII fund. These fund companies receive money subscribed by investors in RMB and convert RMB into US dollars to invest in overseas assets. The crude oil fund is one of them.