diff --git a/mutants/mutant-1/swen90006/machine/Machine.java b/mutants/mutant-1/swen90006/machine/Machine.java
index 9bf57316d1c736ea2bd1c62bd6df3c6c0282f331..2cd411614a8d0f8c30aafc81bef0cb9f52fd0993 100644
--- a/mutants/mutant-1/swen90006/machine/Machine.java
+++ b/mutants/mutant-1/swen90006/machine/Machine.java
@@ -148,7 +148,8 @@ public class Machine
   private void validate_offset(int offset)
     throws InvalidInstructionException
   {
-    if (offset < -MAX_ADDR || offset > MAX_ADDR) {
+      //it was offset < -MAX_ADDR || offset > MAX_ADDR
+    if (offset >= -MAX_ADDR || offset <= MAX_ADDR) {
       throw new InvalidInstructionException();
     }
   }