diff --git a/training-assignments/src/java/eu/sig/training/ch04-duplication/bankaccounts/SavingsAccount.java b/training-assignments/src/java/eu/sig/training/ch04-duplication/bankaccounts/SavingsAccount.java
index 7d1ef65..2aac3d7 100644
--- a/training-assignments/src/java/eu/sig/training/ch04-duplication/bankaccounts/SavingsAccount.java
+++ b/training-assignments/src/java/eu/sig/training/ch04-duplication/bankaccounts/SavingsAccount.java
@@ -1,12 +1,16 @@
 package eu.sig.training.ch04;
 
-// tag::CheckingAccount[]
-public class CheckingAccount {
+// tag::SavingsAccount[]
+public class SavingsAccount {
     private static final float INTEREST_PERCENTAGE = 0.05f;
     private Money balance = new Money();
 
     public Transfer makeTransfer(String counterAccount, Money amount)
         throws BusinessException {
+        // 1. Check if it is the own checkaccount:
+        if (counterAccount =/= SavingsAccount) {
+            throw new BusinessException("Invalid Account!");
+        }
         // 1. Assuming result is 9-digit bank account number, validate 11-test:
         int sum = 0;
         for (int i = 0; i < counterAccount.length(); i++) {