diff --git a/codebook-lvt/src/main/java/io/papermc/codebook/lvt/LvtUtil.java b/codebook-lvt/src/main/java/io/papermc/codebook/lvt/LvtUtil.java
index 9b14777..3696764 100644
--- a/codebook-lvt/src/main/java/io/papermc/codebook/lvt/LvtUtil.java
+++ b/codebook-lvt/src/main/java/io/papermc/codebook/lvt/LvtUtil.java
@@ -138,7 +138,7 @@ public static String parseSimpleTypeName(final String simpleName) {
         // UUID -> uuid
         // AABB -> aabb
         if (LvtUtil.isStringAllUppercase(simpleName)) {
-            return simpleName.toLowerCase();
+            return simpleName.toLowerCase(Locale.ROOT);
         }
 
         // Decapitalize