Regulations
Ringing is done for scientific purposes, and only experienced, licensed ornithologists are allowed to do this. It is the Norwegian Environment Agency that grants a license to the ringing, based on the recommendations of the Ringing Centre.
The rules and regulations that the individual ringer must comply with in order to be able to ring a bird can be found here:
Forskrift om innfanging og innsamling av vilt for vitenskapelige eller andre særlige formål