diff --git a/lib/linguist/documentation.yml b/lib/linguist/documentation.yml
index 99cfe382..1bf4b1ce 100644
--- a/lib/linguist/documentation.yml
+++ b/lib/linguist/documentation.yml
@@ -15,6 +15,7 @@
 - ^[Mm]an/
 - ^[Ee]xamples/
 - ^[Dd]emos?/
+- (^|/)inst/doc/
 
 ## Documentation files ##