Security, Definition

Generally, a transferable instrument representing an ownership interest in a corporation (equity security or stock) or the debt of a corporation, government or organization.

The official definition, from the Securities Exchange Act of 1934, is: "Any note, stock, treasury stock, bond, debenture, certificate of interest or participation in any profit-sharing agreement or in any oil, gas, or other mineral royalty or lease, any collateral trust certificate, preorganization certificate or subscription, transferable share, investment contract, voting-trust certificate, certificate of deposit, for a security, any put, call, straddle, option, or privilege on any security, certificate of deposit, or group or index of securities (including any interest therein or based on the value thereof), or any put, call, straddle, option, or privilege entered into on a national securities exchange relating to foreign currency, or in general, any instrument commonly known as a 'security'; or any certificate of interest or participation in, temporary or interim certificate for, receipt for, or warrant or right to subscribe to or purchase, any of the foregoing; but shall not include currency or any note, draft, bill of exchange, or banker's acceptance which has a maturity at the time of issuance of not exceeding nine months, exclusive of days of grace, or any renewal thereof the maturity of which is likewise limited."

Other forms of debt such as mortgages can be converted into securities. Certain derivatives on securities (e.g., options on equity securities) are also considered securities for the purposes of the securities laws. Security Futures Products are considered to be both securities and futures products. Futures contracts on Broad-Based Securities Indexes are not considered securities.