Anycast is a networking technique that allows multiple machines in different locations to share the same IP address. For example, 8.8.8.8 could route to a server in the US or Europe depending on where the request originates.
Because anycast IPs don't map to a single location, standard geolocation results for these addresses can be unreliable. IPinfo's anycast detection flag identifies when an IP address is anycast, so applications can handle these cases accordingly rather than relying on potentially inaccurate location data.