The so-called customer (deposit) deposit of securities company is a cash deposit that investors can transfer to the stock fund account by bank-securities transfer and can be used for stock trading at any time. Because stock trading needs funds to buy, so the funds are also called trading margin, so the funds that investors put in securities accounts waiting to buy stocks are the customer (deposit) margin of securities companies.
Generally speaking, the customer margin is the available balance of the investor's capital account, and the customer margin of the securities company exists in the investor's capital account.