open box


Open Box

1. The physical location where a brokerage keeps securities being held as collateral on loans. Open boxes are used for collateral on margin accounts and other transactions. See also: Free box.

2. Collateral used to secure funds borrowed on a margin account. A margin account allows an investor to buy securities with money borrowed from a broker; the funds are payable on demand of the broker. They also must be secured by an open box, which usually consists of securities owned by the borrower. The "box" refers to a safe where the stock and bond certificates are kept until the margin account is paid off. An open box in this sense is also called an active box.

open box

The physical location within brokerage firms of securities that are available for use as collateral for loans. Also called active box. Compare free box.