diff --git a/guix/gnu-maintenance.scm b/guix/gnu-maintenance.scm
index 0b5bc8592c..2a4d94dbb0 100644
--- a/guix/gnu-maintenance.scm
+++ b/guix/gnu-maintenance.scm
@@ -240,7 +240,7 @@ network to check in GNU's database."
   (make-regexp "^([^.]+)-([0-9]|[^-])+(-(src|gnu[0-9]))?\\.(tar\\.|zip$)"))
 
 (define %alpha-tarball-rx
-  (make-regexp "^.*-.*[0-9](-|~)?(alpha|beta|rc|cvs|svn|git)-?[0-9\\.]*\\.tar\\."))
+  (make-regexp "^.*-.*[0-9](-|~)?(alpha|beta|rc|RC|cvs|svn|git)-?[0-9\\.]*\\.tar\\."))
 
 (define (release-file? project file)
   "Return #f if FILE is not a release tarball of PROJECT, otherwise return