The margin function of spot crude oil is that the margin does not need to be fully occupied, but it needs to ensure the liquidity of the transaction. Margin is an efficient mechanism, that is, you can borrow money from the brokerage account, but when borrowing money, you need to deposit enough liquidity in the account to ensure that you can bear the potential debt risks.
Spot oil is also called spot crude oil and international crude oil. In China, only the exchange that has passed the corresponding examination and approval can engage in spot trading of crude oil.