diff --git a/core/sysprop.mk b/core/sysprop.mk
index cf4b1f6..8877743 100644
--- a/core/sysprop.mk
+++ b/core/sysprop.mk
@@ -66,9 +66,12 @@
     )\
     echo "ro.$(1).build.date=`$(DATE_FROM_FILE)`" >> $(2);\
     echo "ro.$(1).build.date.utc=`$(DATE_FROM_FILE) +%s`" >> $(2);\
-    echo "ro.$(1).build.fingerprint=$(BUILD_FINGERPRINT_FROM_FILE)" >> $(2);\
-    echo "ro.$(1).build.id=$(BUILD_ID)" >> $(2);\
-    echo "ro.$(1).build.tags=$(BUILD_VERSION_TAGS)" >> $(2);\
+    # Allow optional assignments for ARC forward-declarations (b/249168657)
+    # TODO: Remove any tag-related inconsistencies once the goals from
+    # go/arc-android-sigprop-changes have been achieved.
+    echo "ro.$(1).build.fingerprint?=$(BUILD_FINGERPRINT_FROM_FILE)" >> $(2);\
+    echo "ro.$(1).build.id?=$(BUILD_ID)" >> $(2);\
+    echo "ro.$(1).build.tags?=$(BUILD_VERSION_TAGS)" >> $(2);\
     echo "ro.$(1).build.type=$(TARGET_BUILD_VARIANT)" >> $(2);\
     echo "ro.$(1).build.version.incremental=$(BUILD_NUMBER_FROM_FILE)" >> $(2);\
     echo "ro.$(1).build.version.release=$(PLATFORM_VERSION_LAST_STABLE)" >> $(2);\
@@ -565,4 +568,4 @@
 # $1 installed file path, e.g. out/target/product/vsoc_x86_64/system/build.prop
 define is-build-prop
 $(if $(findstring $1,$(ALL_INSTALLED_BUILD_PROP_FILES)),Y)
-endef
\ No newline at end of file
+endef