diff --git a/src/main/java/net/floodlightcontroller/devicemanager/web/DeviceSerializer.java b/src/main/java/net/floodlightcontroller/devicemanager/web/DeviceSerializer.java
index 4e4e07db9cd73899fef3e9b091d53ac19831b6ef..e946d7b8aa7674ad598ba022e75e556ca9780297 100644
--- a/src/main/java/net/floodlightcontroller/devicemanager/web/DeviceSerializer.java
+++ b/src/main/java/net/floodlightcontroller/devicemanager/web/DeviceSerializer.java
@@ -64,7 +64,10 @@ public class DeviceSerializer extends JsonSerializer<Device> {
 
         jGen.writeNumberField("lastSeen", device.getLastSeen().getTime());
         
-        jGen.writeStringField("dhcpClientName", device.getDHCPClientName());
+        String dhcpClientName = device.getDHCPClientName();
+        if (dhcpClientName != null) {
+            jGen.writeStringField("dhcpClientName", dhcpClientName);
+        }
 
         jGen.writeEndObject();
     }