What are CUSIP numbers?
On the right front side of most modern certificates is a nine-character number called the 'CUSIP' number. CUSIP is an abbreviation for the Committee on Uniform Security Identification Procedures. That committee developed the numbering system to help in the clearing of the tremendous numbers of physical certificates that were traded daily on U.S. and Canadian exchanges.
Today, Standard & Poor’s manages the system and is responsible for assigning new numbers. It also administers a similar nine-character 'CINS' (the CUSIP International Numbering System) numbering system for international issues.
In both systems, the first six characters are unique to specific companies. The next two characters represent specific issues made by that company. The ninth character is a check-digit that allows accuracy checking, regardless of whether the CUSIP number was entered into a tracking system by hand or by optical reader.
In general, all modern issues carry the CUSIP number, even the vast number of government issues. The exceptions are certificates intended to circulate and trade outside of the Clearing House system. These include certificates such as fractional shares and issues produced by small, private placements
The CUSIP system was developed in 1967. There are reports of CUSIP numbers appearing on railroad stock certificates as early as 1969, although the earliest examples I can confirm are dated 1970.
Most companies had their printers pre-print all nine characters of the CUSIP number on their certificates. Less frequently, they pre-printed the first six characters, and added the final three just prior to issuance. In an effort to use their older supplies of certificates, companies sometimes overprinted CUSIP numbers.
To learn more about CUSIP numbers, visit http://www.cusip.com/