The map image on each Neighborhood NFT is custom designed by Mapstone. The exact border shape is provided by the U.S. Census Bureau and is defined as a ZIP Code Tabulation Areas (ZCTA). A ZCTA is a geographic product of the U.S. Census Bureau created to allow mapping, display, and geographic analyses of the United States Postal Service (USPS) Zone Improvement Plan (ZIP) Codes dataset.
The Mapstone royalty payment system for each postal code is determined solely by how that postal code is classified from the 2020 U.S. Census. Postal code borders and shape files provided by the U.S. Census Bureau are updated once every 10 years. If postal code boundaries ever change after an NFT is minted, royalty payments will still be based whichever addresses are within the corresponding postal code, as defined by Mapbox street addresses, not the static border imagery on the NFT.