diff --git a/common/cert_validity.py b/common/cert_validity.py
index 83a765c..ac2b536 100644
--- a/common/cert_validity.py
+++ b/common/cert_validity.py
@@ -1,14 +1,7 @@
-"""
-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.
+# SPDX-FileCopyrightText: 2020 The Magma Authors.
+# SPDX-FileCopyrightText: 2022 Open Networking Foundation <support@opennetworking.org>
+#
+# SPDX-License-Identifier: BSD-3-Clause
 
 Util module to distinguish between the reasons checkins stop working: network
 is down or cert is invalid.