Search notes:

/var/db/repos/gentoo/profiles/license_group

/var/db/repos/gentoo/profiles/license_group stores license groups.
A license group is the first entry of a line where all characters are capital letters. The entries on the line following the license group are the individual licenses: 
GROUPNAME LICENSEONE LICENSETWO …

See also

In the ACCEPT_LICENSE value of /etc/portage/make.conf, a license group is identified by the at sign @.
Licenses are stored in the directory /var/db/repos/gentoo/licenses/.

Index