diff --git a/clif/testing/python/vector_unique_ptr_member.clif b/clif/testing/python/vector_unique_ptr_member.clif
new file mode 100644
index 00000000..20c6adec
--- /dev/null
+++ b/clif/testing/python/vector_unique_ptr_member.clif
@@ -0,0 +1,20 @@
+# Copyright 2023 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from "clif/testing/vector_unique_ptr_member.h":
+  namespace `clif_testing_vector_unique_ptr_member`:
+    class VectorOwner:
+      @classmethod
+      def Create(cls, num_elems: int) -> VectorOwner
+      def data_size(self) -> int
diff --git a/clif/testing/python/vector_unique_ptr_member_test.py b/clif/testing/python/vector_unique_ptr_member_test.py
new file mode 100644
index 00000000..8dca3cfb
--- /dev/null
+++ b/clif/testing/python/vector_unique_ptr_member_test.py
@@ -0,0 +1,30 @@
+# Copyright 2023 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+from absl.testing import absltest
+from absl.testing import parameterized
+
+from clif.testing.python import vector_unique_ptr_member
+
+
+class VectorUniquePtrMemberTest(parameterized.TestCase):
+
+  @parameterized.parameters(range(3))
+  def testCreate(self, num_elems):
+    vo = vector_unique_ptr_member.VectorOwner.Create(num_elems)
+    assert vo.data_size() == num_elems
+
+
+if __name__ == '__main__':
+  absltest.main()
diff --git a/clif/testing/vector_unique_ptr_member.h b/clif/testing/vector_unique_ptr_member.h
new file mode 100644
index 00000000..ee27a518
--- /dev/null
+++ b/clif/testing/vector_unique_ptr_member.h
@@ -0,0 +1,44 @@
+/*
+ * Copyright 2023 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+#ifndef CLIF_TESTING_VECTOR_UNIQUE_PTR_MEMBER_H_
+#define CLIF_TESTING_VECTOR_UNIQUE_PTR_MEMBER_H_
+
+#include <memory>
+#include <vector>
+
+namespace clif_testing_vector_unique_ptr_member {
+
+struct DataType {};
+
+// Reduced from a use case in the wild.
+struct VectorOwner {
+  static std::unique_ptr<VectorOwner> Create(std::size_t num_elems) {
+    return std::unique_ptr<VectorOwner>(
+        new VectorOwner(std::vector<std::unique_ptr<DataType>>(num_elems)));
+  }
+
+  std::size_t data_size() const { return data_.size(); }
+
+ private:
+  explicit VectorOwner(std::vector<std::unique_ptr<DataType>> data)
+      : data_(std::move(data)) {}
+
+  const std::vector<std::unique_ptr<DataType>> data_;
+};
+
+}  // namespace clif_testing_vector_unique_ptr_member
+
+#endif  // CLIF_TESTING_VECTOR_UNIQUE_PTR_MEMBER_H_