[LICENSE] Add SPDX Identifier
diff --git a/utils/examples/xor.sh b/utils/examples/xor.sh
index eb98446..474dcfe 100755
--- a/utils/examples/xor.sh
+++ b/utils/examples/xor.sh
@@ -12,6 +12,7 @@
 # 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-License-Identifier: Apache-2.0
 
 
 : ${1?"Usage: $0 file1.gds file2.gds <top_level_module_name>"}