Rat warehouse refers to the banker who uses his own personal funds (heads of institutions, traders and their relatives, related households) to open a warehouse at a low level before raising the stock price with public funds. After the public funds are raised to a high level, individual positions are sold first to make a profit. Generally speaking, you ask the dealer to buy stocks on your behalf, and the dealer buys stocks with his own money when the price is low. When the raised funds are used to buy stocks, according to the relationship between supply and demand, the stock price rises, and the higher the stock price, the more people buy. At this time, the dealer will secretly sell his own stock. After the brokers found out, they sold a lot of stocks, and the supply exceeded the demand, which led to the stock price falling and the brokers lost money.