This filter screens the Ship To and Bill To addresses (street number, street name, state, and ZIP code) against the United States Postal Service database of existing addresses. The USPS updates the database continually.
The specified action is taken whenever the address cannot be validated (it does not exist or is incorrect in some way).
The filter does not validate that the person named in the transaction data lives at that address or even that the address is currently occupied—only that the address exists in the database.
To trick a merchant’s filters, fraudsters sometimes deliberately misspell or make up street names. This enables the fraudster to spoof AVS, geo-location, and high-risk address filters. You can intercept this basic form of spoofing by using the USPS Address Validation filter to determine whether an address really exists.
One useful side effect of the filter is that flagrantly mis-keyed addresses of legitimate customers can be identified before shipping.