diff --git a/build_library/grub.cfg b/build_library/grub.cfg
index 79bb971e31..2223dd1a9d 100644
--- a/build_library/grub.cfg
+++ b/build_library/grub.cfg
@@ -72,8 +72,9 @@ if [ -n "$first_boot" ]; then
     set first_boot="coreos.first_boot=1 coreos.randomize_disk_guid=00000000-0000-0000-0000-000000000001"
 fi
 
+set oem=""
 if [ -n "$oem_id" ]; then
-    set oem_id="coreos.oem.id=$oem_id"
+    set oem="coreos.oem.id=$oem_id"
 fi
 
 # If no specific console has been set by the OEM then select based on
@@ -105,7 +106,7 @@ if [ "$grub_platform" = efi ]; then
 fi
 
 # Assemble the options applicable to all the kernels below
-set linux_cmdline="rootflags=rw mount.usrflags=ro consoleblank=0 $linux_root $linux_console $first_boot $oem_id $linux_append"
+set linux_cmdline="rootflags=rw mount.usrflags=ro consoleblank=0 $linux_root $linux_console $first_boot $oem $linux_append"
 
 # Re-implement grub_abort() since no command exposes it.
 function abort {