The main business of securities companies is to provide securities brokers (simply speaking, they are buying and selling stocks as agents, and customers are retail investors and funds) and investment banks (IPO, mergers and acquisitions, bond issuance and underwriting, etc.). ), asset management (that is, investing customers' funds and distributing profits to customers), self-management (investing with their own money) and research institutes (providing sellers' reports).

Fund companies are divided into Public Offering of Fund and private equity funds. Traditionally, publicly issued funds only invest in securities, such as stocks and bonds. Private equity funds are divided into private equity investment funds and private equity funds, the former mainly invests in the securities market; The latter mainly invests in the equity of non-listed companies.

Closed-end fund:

Because closed-end funds are traded by bidding in securities trading, the transaction price is affected by the relationship between market supply and demand, which does not necessarily reflect the fund's net asset value, that is, the transaction price of closed-end funds has a premium and discount phenomenon relative to its net asset value.

The practice of foreign closed-end funds shows that the transaction price often has the price fluctuation law of first premium and then discount. Judging from the operation of closed-end funds in China, no matter how the fundamental situation changes, the transaction price trend of closed-end funds in China has never deviated from the price fluctuation law of first premium and then discount.