diff --git a/meta-signing-key/conf/layer.conf b/meta-signing-key/conf/layer.conf
index fe551d8..ab5112f 100644
--- a/meta-signing-key/conf/layer.conf
+++ b/meta-signing-key/conf/layer.conf
@@ -53,7 +53,7 @@ BOOT_KEYS_DIR ??= "${SAMPLE_BOOT_KEYS_DIR}"
 GRUB_PUB_KEY ??= "${BOOT_KEYS_DIR}/boot_pub_key"
 
 # Define the identification of vendor
-VENDOR_UUID = "1f7b9654-2107-4697-8f1c-0cbc38874588"
+VENDOR_UUID ??= "1f7b9654-2107-4697-8f1c-0cbc38874588"
 
 # User configurable identification of signature owner 
 UEFI_SIG_OWNER_GUID ??= "${VENDOR_UUID}"