diff --git a/com/Acrobot/ChestShop/Signs/ChestShopSign.java b/com/Acrobot/ChestShop/Signs/ChestShopSign.java
index 436fa10..37e58b2 100644
--- a/com/Acrobot/ChestShop/Signs/ChestShopSign.java
+++ b/com/Acrobot/ChestShop/Signs/ChestShopSign.java
@@ -40,7 +40,8 @@ public class ChestShopSign {
     }
 
     public static boolean isValid(String[] line) {
-        return isValidPreparedSign(line) && (line[2].contains("B") || line[2].contains("S")) && !line[0].isEmpty();
+        return isValidPreparedSign(line) && (line[2].toUpperCase().contains("B") || line[2].toUpperCase().contains("S")) && !line[0].isEmpty();
+
     }
 
     public static boolean isValid(Block sign) {