diff --git a/tools/buildinfo.sh b/tools/buildinfo.sh
index c2e36df..0ed9453 100755
--- a/tools/buildinfo.sh
+++ b/tools/buildinfo.sh
@@ -7,9 +7,9 @@
 if [ "$BOARD_USE_VBMETA_DIGTEST_IN_FINGERPRINT" = "true" ] ; then
   echo "ro.build.legacy.id=$BUILD_ID"
 else
-  echo "ro.build.id=$BUILD_ID"
+  echo "ro.build.id?=$BUILD_ID"
 fi
-echo "ro.build.display.id=$BUILD_DISPLAY_ID"
+echo "ro.build.display.id?=$BUILD_DISPLAY_ID"
 echo "ro.build.version.incremental=$BUILD_NUMBER"
 echo "ro.build.version.sdk=$PLATFORM_SDK_VERSION"
 echo "ro.build.version.preview_sdk=$PLATFORM_PREVIEW_SDK_VERSION"
@@ -28,7 +28,9 @@
 echo "ro.build.type=$TARGET_BUILD_TYPE"
 echo "ro.build.user=$BUILD_USERNAME"
 echo "ro.build.host=$BUILD_HOSTNAME"
-echo "ro.build.tags=$BUILD_VERSION_TAGS"
+# TODO: Remove any tag-related optional property declarations once the goals
+# from go/arc-android-sigprop-changes have been achieved.
+echo "ro.build.tags?=$BUILD_VERSION_TAGS"
 echo "ro.build.flavor=$TARGET_BUILD_FLAVOR"
 
 # These values are deprecated, use "ro.product.cpu.abilist"
@@ -49,7 +51,7 @@
 echo "ro.build.product=$TARGET_DEVICE"
 
 echo "# Do not try to parse description or thumbprint"
-echo "ro.build.description=$PRIVATE_BUILD_DESC"
+echo "ro.build.description?=$PRIVATE_BUILD_DESC"
 if [ -n "$BUILD_THUMBPRINT" ] ; then
   echo "ro.build.thumbprint=$BUILD_THUMBPRINT"
 fi