Copyright-holder and year information is extracted from git log. git history begins in 2005. So (C) from 1998..2005 is lost. Also some (C) assignment of commits where the committer didn't use --author.
Paul Davis was responsible for introducing almost all of this.
git-svn-id: svn://localhost/ardour2/branches/3.0@14190 d708f5d6-7413-0410-9779-e7cbd77b26cf