LICENSE and COPYRIGHT tags on VorbisComments
Currently, these may be used on Vorbis, Speex, FLAC, and Theora as these formats are compatible with the VorbisComments schema.
VorbisComments is a simple tagging format, and not a metadata system, and is stored inside files. It may be compared with ID3, but in opposition to it, VorbisComments are a clear and coherent standard, and not a pile of hacks. VorbisComments are written in UPPER CASE.
To put a license on a file which you are entitled the copyright of, use the LICENSE and COPYRIGHT tags.
The LICENSE tag must store an URI pointing to the relevant license documentation.
The COPYRIGHT tag must store the name of the authoring person or entity. A date should not be stored here, as a DATE tag already exists.