Over-the-counter (OTC) or off-exchange trading or pink sheet trading is done directly between two parties, without the supervision of an exchange. It is contrasted with exchange trading, which occurs via exchanges. A stock exchange has the benefit of facilitating liquidity, providing transparency, and maintaining the current market price. In an OTC trade, the price is not necessarily publicly disclosed.
OTC trading, as well as exchange trading, occurs with commodities, financial instruments (including stocks), and derivatives of such products. Products traded on traditional stock exchanges, and other regulated bourse platforms, must be well standardized. This means that exchanged deliverables match a narrow range of quantity, quality, and identity which is defined by the exchange and identical to all transactions of that product. This is necessary for there to be transparency in stock exchange-based equities trading.