Limit Order Information System - LOIS

An electronic system used by specialists in the stock market. A limit order information system lists price and size quotes for exchange-listed securities. The data produced by this system is used by subscribers and specialists to locate the most opportunistic market for making a trade because the service distributes information about where a security is traded, order quantities, and bid and offer prices.

Taobiz explains Limit Order Information System - LOIS

This system is used to locate the best securities prices available and produces information about securities traded on participating exchanges like the Nasdaq and NYSE. A limit order is an order to buy or sell a stock at a specific price, and includes information such as order quantities, bid price, offer and the exchange on which the security is listed. Limit orders help protect buyers or sellers of a stock from selling at a price that is higher or lower than desired.