[LICENSE] Add SPDX Identifier
diff --git a/utils/gds2mag-mag.local.sh b/utils/gds2mag-mag.local.sh
index c914f70..5f55959 100755
--- a/utils/gds2mag-mag.local.sh
+++ b/utils/gds2mag-mag.local.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
 
 export PDK_ROOT=~/foss/pdks/open_pdks/sky130;
 export MAGTYPE=mag ;