Dual address information is passed to the US Postal Matcher from the Customer Data Parser using the us_gin area. The following rules describe how a dual address is handled:
Rule 1
If one of the addresses is general delivery, then us_gin_street_name contains the other address, and a 'G' is set in the first position of us_gin_dual_addr_flag.
Rule 2
If one of the addresses is a post office box, then us_gin_street_name contains the other address, and a 'P' is set in the first position of us_gin_dual_addr_flag. The PO box number is also stored, starting at the second position of us_gin_box_number.
Rule 3
If the dual address contains both a general delivery address and a PO box number, then 'PO BOX' is stored in us_gin_street_name, and a 'G' is set in the first position of us_gin_dual_addr_flag.
Rule 4
If the dual address contains both a street name and a rural route, then the street name is stored in us_gin_street_name, and an 'R' is stored in the first position of us_gin_dual_addr_flag. In addition, the route number is stored in us_gin_route_number and the box number is stored in us_gin_box_number.
The following table shows where dual address information is stored:
| Address | us_gin_street_name | us_gin_dual_addr_flag | us_gin_route_number | us_gin_box_number | |
|---|---|---|---|---|---|
| 1 | street name / general delivery | street name | G | ||
| 2 | general delivery / street name | street name | G | ||
| 3 | street name / PO box | street name | P | PO box number | |
| 4 | PO box / street name | street name | P | PO box number | |
| 5 | general delivery / PO box | PO box | G | ||
| 6 | PO box / general delivery | PO box | G | ||
| 7 | rural route / general delivery | rural route | G | ||
| 8 | general delivery / rural route | rural route | G | ||
| 9 | rural route / PO box | rural route | P | PO box number | |
| 10 | PO box / rural route | rural route | P | PO box number | |
| 11 | street name / rural route | street name | R | route number | PO box number |
| 12 | rural route / street name | street name | R | route number | PO box number |