diff --git a/include/pybind11/cast.h b/include/pybind11/cast.h
index 94d3e03..8684d7c 100644
--- a/include/pybind11/cast.h
+++ b/include/pybind11/cast.h
@@ -919,6 +919,9 @@
             return true;
         }
 
+        if (typeinfo->default_holder)
+            throw cast_error("Unable to load a custom holder type from a default-holder instance");
+
         if (typeinfo->simple_type) { /* Case 1: no multiple inheritance etc. involved */
             /* Check if we can safely perform a reinterpret-style cast */
             if (PyType_IsSubtype(tobj, typeinfo->type))
diff --git a/tests/test_smart_ptr.cpp b/tests/test_smart_ptr.cpp
index ca28dac..83c1c01 100644
--- a/tests/test_smart_ptr.cpp
+++ b/tests/test_smart_ptr.cpp
@@ -265,4 +265,10 @@
 
     py::class_<C, CustomUniquePtr<C>>(m, "TypeWithMoveOnlyHolder")
         .def_static("make", []() { return CustomUniquePtr<C>(new C); });
+
+    struct HeldByDefaultHolder { };
+
+    py::class_<HeldByDefaultHolder>(m, "HeldByDefaultHolder")
+        .def(py::init<>())
+        .def_static("load_shared_ptr", [](std::shared_ptr<HeldByDefaultHolder>) {});
 });
diff --git a/tests/test_smart_ptr.py b/tests/test_smart_ptr.py
index 6a617f7..b5af3bd 100644
--- a/tests/test_smart_ptr.py
+++ b/tests/test_smart_ptr.py
@@ -211,3 +211,12 @@
     assert stats.alive() == 1
     del a
     assert stats.alive() == 0
+
+
+def test_smart_ptr_from_default():
+    from pybind11_tests.smart_ptr import HeldByDefaultHolder
+
+    instance = HeldByDefaultHolder()
+    with pytest.raises(RuntimeError) as excinfo:
+        HeldByDefaultHolder.load_shared_ptr(instance)
+    assert "Unable to load a custom holder type from a default-holder instance" in str(excinfo)