Invoice Number To create the invoice number (INVN), CyberSource does the following: 1 Chooses a date to use. If the airline invoice date was sent in the request, CyberSource uses that date. Otherwise, CyberSource uses the creation date, which is the date the batch file was generated. The field name for the airline invoice date is airline_invoice_date. Concatenates the following 14 characters: 3 characters 2 characters 3 characters 4 characters 2 characters Airline code Year from the chosen date;example: 06 for 2006 Day of year from the chosen date; example: 000 for January 1 Acquirer: the left-most 4 digits of the card number Spaces