A temporary identification number attached to a security by a company until the official CUSIP number is assigned. Committee on Uniform Securities Identification Procedures numbers identify securities when recording buy and sell orders. A dummy CUSIP number is a nine-character code for internal company use but may never actually be changed to an official identifier. Dummy CUSIP numbers may also be assigned to securities that are no longer in existence.
Taobiz explains Dummy CUSIP Number
The nine-digit dummy cusip numbers are supplied by the CUSIP Service Bureau . The first six characters identify the issuer, the next two describe the issue and the last character is used as a mathematical check for accuracy. The fourth, fifth and seventh characters are always nines .