diff --git a/lib/linguist/documentation.yml b/lib/linguist/documentation.yml
index 57fc6151..b884cd35 100644
--- a/lib/linguist/documentation.yml
+++ b/lib/linguist/documentation.yml
@@ -14,5 +14,6 @@
 
 - (^|/)CONTRIBUTING(\.|$)
 - (^|/)COPYING(\.|$)
+- (^|/)INSTALL(\.|$)
 - (^|/)LICEN[CS]E(\.|$)
 - (^|/)README(\.|$)
diff --git a/test/test_blob.rb b/test/test_blob.rb
index 24eaff83..149588e9 100644
--- a/test/test_blob.rb
+++ b/test/test_blob.rb
@@ -470,6 +470,11 @@ class TestBlob < Minitest::Test
     assert_predicate fixture_blob("COPYING.txt"), :documentation?
     assert_predicate fixture_blob("foo/COPYING"), :documentation?
 
+    assert_predicate fixture_blob("INSTALL"), :documentation?
+    assert_predicate fixture_blob("INSTALL.md"), :documentation?
+    assert_predicate fixture_blob("INSTALL.txt"), :documentation?
+    assert_predicate fixture_blob("foo/INSTALL"), :documentation?
+
     refute_predicate fixture_blob("foo.md"), :documentation?
   end