TBA CUSIP Format
There is a special assignment of CUSIP numbers for TBA Security. Working with the MBSCC, CUSIP Global Services (CGS) developed a specialized identification scheme for TBA (To Be Announced) mortgage-backed securities.
TBA CUSIPs incorporate, within the identifier itself, a security’s mortgage type (Ginnie Mae, Fannie Mae,Freddie Mac), coupon, maturity and settlement month.
TBA Algorithm:
Position 1-2: Product Code (e.g. Single Family Mortgage, ARM, Balloon, etc.)
Position 3: Type of Mortgage (Ginnie Mae, Fannie Mae, Freddie Mac)
Position 4-6: Coupon
Position 7: Maturity
Position 8: Settlement Month
Position 9: Check Digit
The exact values for each position are available in a spreadsheet called the TBA Grid.
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