After Hours Trading
The practice of trading a security after an exchange has closed. After-hours trading occurs over-the-counter, but both listed and unlisted securities may be traded. After-hours trading is often less liquid than regular trading because participation by market makers is voluntary, whereas market makers are required to serve as a counterparty for a security during trading hours. The price of a security in after-hours trading may influence is price on the next trading day. The practice is less commonly called extended-hours trading.
See after-hours trading.