There are two situations in which the exchange implements compulsory lightening: compulsory lightening in the case of continuous ups and downs and compulsory lightening in the case of policies. If the former is expressly stipulated in the trading rules of the exchange, it shall be implemented in accordance with the provisions; The latter is mostly due to the risk control measures taken by the competent authorities (CSRC) on the futures market, such as the plywood incident of Shanghai Commodity Exchange 1995, the red bean incident of Suzhou Exchange 1996 and the mung bean incident of Zhengzhou Exchange 1999. According to the current trading rules of various exchanges, when there is a continuous price limit, the exchange will implement compulsory lightening measures. Specifically, after the end of the day's trading, the list that was quoted at the daily limit (or daily limit) but failed to close the position was forcibly closed, and the opponent who closed the position was the list that held the profit of the contract. The principle of closing positions is to start with the most profitable list until all pending orders (hanging at the stop-loss price) that have not been closed (before closing positions) are closed.

As can be seen from the above: the executor of compulsory lightening is the exchange; The price of lightening the position is the daily limit (or daily limit); Whether you are willing to lighten your position voluntarily or not, as long as your position is profitable, it may be closed. The principle is "the more profitable, the more likely it is to be crushed". If the net position of a customer holding a two-way position is profitable, it may be closed. However, two-way positions will not force liquidation, except for policy positions. The net position profit of each trader is easy to calculate, just like the customer's list, so there is basically no need for manual intervention when closing the position forcibly. The trading system of the exchange will automatically select the list with the most profit (position profit and loss) and the open pending order. The theoretical starting point of the exchange's forced liquidation is: for the orderly development of the industry, profitable customers give up a little interest, so that loss-making customers lose less, so that this market can run healthily and for a long time.