Sometimes it is necessary to re-license files containing code or documentation for a variety of reasons. This usually is the case for somewhat older files and often the contributors to that file never intended to use a license incompatible with the KDE Licensing Policy.
To re-license such a file, you will have to ask each and every contributor to that file if they agree to their work being re-licensed. You can only proceed with the re-licensing if you have approval from all contributors to the file (with no exceptions).
Before doing so, please send copies of the appropriate emails to sysadmin, so we can archive these mails in a special archive which is kept private and only accessible by sysadmins. This allows us to provide the approval mails as needed in the future if someone has questions about the re-licensing of files.
In certain special circumstances, the KDE Community may be given permission by code authors to relicense files en-masse. Such cases are always specially documented. For example, many authors have given permission to KDE to relicense their code from GPLv2 and LGPLv2 to GPLv2+, GPLv3, LGPLv2+ and LGPLv3. The permissions that were granted are fully documented on the KDE Techbase Wiki.