Centralized bidding for foreign exchange transactions refers to the way in which multiple trading entities in the market conduct foreign exchange transactions through a trading system or platform at the same time according to certain bidding rules. For example, at present, the transaction mode of China's inter-bank foreign exchange market is based on the bidding rules of time priority and price priority. Centralized bidding transaction is a trading method of securities trading in stock exchange. At present, both Shanghai Stock Exchange and Shenzhen Stock Exchange adopt this trading method. Generally speaking, it refers to the situation that two or more buyers and two or more sellers determine the buying and selling prices of securities through public bidding. In this form, there is competition between buyers and sellers, and there are more people on both sides. In centralized bidding, when the highest quotation of the buyer's personnel is consistent with the lowest quotation of the seller's personnel, the transaction price of the securities has been determined and the transaction can be reached. Centralized bidding transactions can be divided into oral bidding transactions, written bidding transactions and computer bidding transactions. Ps: Centralized bidding includes call auction and continuous bidding, which is different from call auction. Among them, the Shanghai Stock Exchange stipulates that the opening price shall be obtained by call auction method from 9: 05 to 9: 25, and the Shenzhen Stock Exchange stipulates that the continuous bidding method shall be adopted from 9: 30 to1:30, 13: 00 to 15: 00.