Block trade
A block trade is a permissible, noncompetitive, privately negotiated transaction either at or exceeding an exchange determined minimum threshold quantity of shares, which is executed apart and away from the open outcry or electronic markets. Major broker-dealers often provide “block trading” services—sometimes known as “upstairs trading desks”—to their institutional clients. In the United States and Canada a block trade is usually at least 10,000 shares of a stock or $100,000 of bonds but in practice significantly larger.