If you open an account with a futures company, they will give you a capital account number 00888 (this account number will only be used when you trade in the company), and a company will apply for your customer number (called customer code in the industry) in Shanghai Futures Exchange, Zhengzhou Commodity Exchange and Dalian Commodity Exchange respectively, assuming that the customer numbers applied for in the three exchanges are 0022 1, 00558 and 065438 respectively.

Then, because the service quality of company A is not satisfactory (slow market speed, lack of information, etc. ), you opened another account in company B, but the account opened in company A was not closed. Then Company B will also apply for your customer number in various exchanges, but because Company A has applied for your customer number in the exchange before, when Company B applies, the exchange will find out your existing customer number (individual customers need to apply for your customer number with an ID card, and the ID card number is unique). In this way, when you trade in company B, the exchange will record all your transactions on your existing customer number.

If you have some trading funds in both Company A and Company B, you can trade in both companies at the same time. Transactions on the same exchange are all reflected in a unique customer number.