diff --git a/test/blackbox-tests/jbuild b/test/blackbox-tests/jbuild
index 11e912a7..8aa5fe21 100644
--- a/test/blackbox-tests/jbuild
+++ b/test/blackbox-tests/jbuild
@@ -338,3 +338,13 @@
       (progn
        (run ${exe:cram.exe} run.t)
        (diff? run.t run.t.corrected))))))))
+
+(alias
+ ((name runtest)
+  (deps ((files_recursively_in test-cases/odoc-unique-mlds)))
+  (action
+   (chdir test-cases/odoc-unique-mlds
+    (setenv JBUILDER ${bin:jbuilder}
+     (progn
+      (run ${exe:cram.exe} -ocamlv ${ocaml_version} -skip-versions 4.02.3 run.t)
+      (diff? run.t run.t.corrected)))))))
diff --git a/test/blackbox-tests/test-cases/odoc-unique-mlds/diff-scope/scope1/foo.mld b/test/blackbox-tests/test-cases/odoc-unique-mlds/diff-scope/scope1/foo.mld
new file mode 100644
index 00000000..e69de29b
diff --git a/test/blackbox-tests/test-cases/odoc-unique-mlds/diff-scope/scope1/jbuild b/test/blackbox-tests/test-cases/odoc-unique-mlds/diff-scope/scope1/jbuild
new file mode 100644
index 00000000..d7f98d26
--- /dev/null
+++ b/test/blackbox-tests/test-cases/odoc-unique-mlds/diff-scope/scope1/jbuild
@@ -0,0 +1,5 @@
+(jbuild_version 1)
+
+(library
+ ((name scope1)
+  (public_name scope1)))
diff --git a/test/blackbox-tests/test-cases/odoc-unique-mlds/diff-scope/scope1/scope1.opam b/test/blackbox-tests/test-cases/odoc-unique-mlds/diff-scope/scope1/scope1.opam
new file mode 100644
index 00000000..e69de29b
diff --git a/test/blackbox-tests/test-cases/odoc-unique-mlds/diff-scope/scope2/foo.mld b/test/blackbox-tests/test-cases/odoc-unique-mlds/diff-scope/scope2/foo.mld
new file mode 100644
index 00000000..e69de29b
diff --git a/test/blackbox-tests/test-cases/odoc-unique-mlds/diff-scope/scope2/jbuild b/test/blackbox-tests/test-cases/odoc-unique-mlds/diff-scope/scope2/jbuild
new file mode 100644
index 00000000..4294bbcd
--- /dev/null
+++ b/test/blackbox-tests/test-cases/odoc-unique-mlds/diff-scope/scope2/jbuild
@@ -0,0 +1,5 @@
+(jbuild_version 1)
+
+(library
+ ((name scope2)
+  (public_name scope2)))
\ No newline at end of file
diff --git a/test/blackbox-tests/test-cases/odoc-unique-mlds/diff-scope/scope2/scope2.opam b/test/blackbox-tests/test-cases/odoc-unique-mlds/diff-scope/scope2/scope2.opam
new file mode 100644
index 00000000..e69de29b
diff --git a/test/blackbox-tests/test-cases/odoc-unique-mlds/run.t b/test/blackbox-tests/test-cases/odoc-unique-mlds/run.t
new file mode 100644
index 00000000..810bbbdd
--- /dev/null
+++ b/test/blackbox-tests/test-cases/odoc-unique-mlds/run.t
@@ -0,0 +1,35 @@
+Duplicate mld's in the same scope
+  $ $JBUILDER build @doc -j1 --display short --root ./same-scope 2>&1 | grep -v Entering
+          odoc _doc/odoc.css
+          odoc _doc/root.lib1/page-index.odoc
+          odoc _doc/root.lib1/page-test.odoc
+        ocamlc lib1/.root_lib1.objs/root_lib1.{cmi,cmo,cmt}
+          odoc _doc/root.lib2/page-index.odoc
+          odoc _doc/root.lib2/page-test.odoc
+        ocamlc lib2/.root_lib2.objs/root_lib2.{cmi,cmo,cmt}
+          odoc _doc/root.lib1/root_lib1.odoc
+          odoc _doc/root.lib2/root_lib2.odoc
+          odoc _doc/root.lib1/index.html
+          odoc _doc/root.lib1/test.html
+          odoc _doc/root.lib1/Root_lib1/.jbuilder-keep,_doc/root.lib1/Root_lib1/index.html
+          odoc _doc/root.lib2/index.html
+          odoc _doc/root.lib2/test.html
+          odoc _doc/root.lib2/Root_lib2/.jbuilder-keep,_doc/root.lib2/Root_lib2/index.html
+
+Duplicate mld's in different scope
+  $ $JBUILDER build @doc -j1 --display short --root ./diff-scope 2>&1 | grep -v Entering
+          odoc _doc/odoc.css
+          odoc _doc/scope1/page-foo.odoc
+          odoc _doc/scope1/page-index.odoc
+        ocamlc scope1/.scope1.objs/scope1.{cmi,cmo,cmt}
+          odoc _doc/scope2/page-foo.odoc
+          odoc _doc/scope2/page-index.odoc
+        ocamlc scope2/.scope2.objs/scope2.{cmi,cmo,cmt}
+          odoc _doc/scope1/scope1.odoc
+          odoc _doc/scope2/scope2.odoc
+          odoc _doc/scope1/foo.html
+          odoc _doc/scope1/index.html
+          odoc _doc/scope1/Scope1/.jbuilder-keep,_doc/scope1/Scope1/index.html
+          odoc _doc/scope2/foo.html
+          odoc _doc/scope2/index.html
+          odoc _doc/scope2/Scope2/.jbuilder-keep,_doc/scope2/Scope2/index.html
diff --git a/test/blackbox-tests/test-cases/odoc-unique-mlds/same-scope/lib1/jbuild b/test/blackbox-tests/test-cases/odoc-unique-mlds/same-scope/lib1/jbuild
new file mode 100644
index 00000000..5d1729dd
--- /dev/null
+++ b/test/blackbox-tests/test-cases/odoc-unique-mlds/same-scope/lib1/jbuild
@@ -0,0 +1,5 @@
+(jbuild_version 1)
+
+(library
+ ((name root_lib1)
+  (public_name root.lib1)))
diff --git a/test/blackbox-tests/test-cases/odoc-unique-mlds/same-scope/lib1/test.mld b/test/blackbox-tests/test-cases/odoc-unique-mlds/same-scope/lib1/test.mld
new file mode 100644
index 00000000..e69de29b
diff --git a/test/blackbox-tests/test-cases/odoc-unique-mlds/same-scope/lib2/jbuild b/test/blackbox-tests/test-cases/odoc-unique-mlds/same-scope/lib2/jbuild
new file mode 100644
index 00000000..e32ea1bc
--- /dev/null
+++ b/test/blackbox-tests/test-cases/odoc-unique-mlds/same-scope/lib2/jbuild
@@ -0,0 +1,5 @@
+(jbuild_version 1)
+
+(library
+ ((name root_lib2)
+  (public_name root.lib2)))
diff --git a/test/blackbox-tests/test-cases/odoc-unique-mlds/same-scope/lib2/test.mld b/test/blackbox-tests/test-cases/odoc-unique-mlds/same-scope/lib2/test.mld
new file mode 100644
index 00000000..e69de29b
diff --git a/test/blackbox-tests/test-cases/odoc-unique-mlds/same-scope/root.opam b/test/blackbox-tests/test-cases/odoc-unique-mlds/same-scope/root.opam
new file mode 100644
index 00000000..e69de29b