diff --git a/tr069/tests/models_tests.py b/tr069/tests/models_tests.py
new file mode 100644
index 0000000..faa76ff
--- /dev/null
+++ b/tr069/tests/models_tests.py
@@ -0,0 +1,74 @@
+"""
+Copyright 2020 The Magma Authors.
+
+This source code is licensed under the BSD-style license found in the
+LICENSE file in the root directory of this source tree.
+
+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.
+"""
+import unittest
+
+from tr069.models import DeviceIdStruct
+from spyne import ComplexModelBase
+
+
+class DeviceIdStructTests(unittest.TestCase):
+    def test_as_dict_memory_leak(self):
+        """
+        Test to ensure as_dict() doesn't leak model instances
+        """
+        thing = DeviceIdStruct(
+            Manufacturer='abc',
+            OUI='def',
+            ProductClass='ghi',
+            SerialNumber='jkl',
+        )
+        res = thing.as_dict()
+        self.assertEqual(
+            {
+                'Manufacturer': 'abc',
+                'OUI': 'def',
+                'ProductClass': 'ghi',
+                'SerialNumber': 'jkl',
+            },
+            res,
+        )
+        # inspect the spyne.util.memoize object that wraps the staticmethod
+        self.assertEqual(1, len(ComplexModelBase.get_flat_type_info.memo))
+
+        # should produce a different result and not grow the size of memo
+        thing.OUI = 'aaaa'
+        res = thing.as_dict()
+        self.assertEqual(
+            {
+                'Manufacturer': 'abc',
+                'OUI': 'aaaa',
+                'ProductClass': 'ghi',
+                'SerialNumber': 'jkl',
+            },
+            res,
+        )
+        self.assertEqual(1, len(ComplexModelBase.get_flat_type_info.memo))
+
+        # use a different object this time. Again should not grow memo
+        thing = DeviceIdStruct(
+            Manufacturer='abc',
+            OUI='def',
+            ProductClass='ghi',
+            SerialNumber='jkl',
+        )
+        res = thing.as_dict()
+        self.assertEqual(
+            {
+                'Manufacturer': 'abc',
+                'OUI': 'def',
+                'ProductClass': 'ghi',
+                'SerialNumber': 'jkl',
+            },
+            res,
+        )
+        self.assertEqual(1, len(ComplexModelBase.get_flat_type_info.memo))