diff --git a/spec/build/bsps/microblaze/microblaze_fpga/optusefdt.yml b/spec/build/bsps/microblaze/microblaze_fpga/optusefdt.yml
index 47cd9cf9f1..7e75d59740 100644
--- a/spec/build/bsps/microblaze/microblaze_fpga/optusefdt.yml
+++ b/spec/build/bsps/microblaze/microblaze_fpga/optusefdt.yml
@@ -8,7 +8,6 @@ copyrights:
 default:
 - enabled-by: true
   value: true
-default-by-variant: []
 description: |
   define if FDT is used
 enabled-by: true