Alternative Trading Systems (ATSs) are electronic trading platforms that connect buyers and sellers of securities that do not take place on traditional stock exchanges. ATSs are typically operated by broker-dealers and are subject to Securities and Exchange Commission oversight (SEC). Dark pools and electronic communication networks are examples of ATSs (ECNs). ATSs can offer a variety of advantages, including increased liquidity and lower transaction costs. They can also provide traders with access to a broader range of securities and provide an alternative way for businesses to raise capital. However, there are concerns that ATSs could be used for insider trading or other forms of market manipulation.

Alternative Trading Systems (ATSs) are electronic platforms that facilitate the buying and selling of financial securities outside of traditional stock exchanges. They are commonly used for trading assets such as stocks, bonds, and other financial instruments. Unlike regular exchanges, ATSs provide a more flexible trading environment and can process transactions more efficiently. A well-known form of ATS is the dark pool, which allows large institutional investors to execute big trades anonymously, helping them avoid drawing attention to their trading activity. This can reduce sudden price movements in the market. While ATSs are regulated by financial authorities, they usually operate under lighter regulatory rules compared to formal exchanges. They have become an important part of modern financial markets by increasing liquidity and offering alternative trading opportunities. However, one drawback is that they may lower market transparency, as some trades occur privately and are not immediately visible to the wider investing public.