diff --git a/mutants/mutant-4/swen90006/machine/Machine.java b/mutants/mutant-4/swen90006/machine/Machine.java
index ec43da69c574ecef7b1bb5994c7fac52d9905525..ba00f5e1cdf39dd40af2ea0d943cc2b1f7a02c91 100644
--- a/mutants/mutant-4/swen90006/machine/Machine.java
+++ b/mutants/mutant-4/swen90006/machine/Machine.java
@@ -148,7 +148,7 @@ public class Machine
   private void validate_offset(int offset)
     throws InvalidInstructionException
   {
-    if (offset < -MAX_ADDR || offset > MAX_ADDR) {
+    if (offset <= -MAX_ADDR || offset > MAX_ADDR) {
       throw new InvalidInstructionException();
     }
   }
@@ -198,7 +198,7 @@ public class Machine
       toks = inst.split("\\s+");
 
       /* check minimum number of tokens */
-      if (toks.length < 1){
+      if (toks.length < 2){
 	throw new InvalidInstructionException();
       }