diff --git a/internal/db/migrations/098_submission_codes_prefix_and_rename.up.sql b/internal/db/migrations/098_submission_codes_prefix_and_rename.up.sql
index 6980afe..4df6f16 100644
--- a/internal/db/migrations/098_submission_codes_prefix_and_rename.up.sql
+++ b/internal/db/migrations/098_submission_codes_prefix_and_rename.up.sql
@@ -240,13 +240,17 @@ BEGIN
             v_bad_shape;
     END IF;
 
-    -- 6.2 No NULL submission_code on active+published rows. The column
-    --     is nullable for legacy reasons, but every live row should
-    --     carry a code after the prefix step.
+    -- 6.2 No NULL submission_code on active+published rows that BELONG
+    --     to a proceeding. Orphan rows (`proceeding_type_id IS NULL`)
+    --     are cross-cutting rules without a fixed proceeding home
+    --     (Wiedereinsetzung, Schriftsatznachreichung, etc.) — they
+    --     legitimately carry NULL submission_code because there's no
+    --     proceeding to prefix with. Exempt them.
     SELECT count(*) INTO v_null_codes
       FROM paliad.deadline_rules
      WHERE is_active = true
        AND lifecycle_state = 'published'
+       AND proceeding_type_id IS NOT NULL
        AND submission_code IS NULL;
     IF v_null_codes <> 0 THEN
         RAISE EXCEPTION