diff --git a/hardware/arduino/sam/cores/arduino/Arduino.h b/hardware/arduino/sam/cores/arduino/Arduino.h
index 4fae76a2a..6194bcc2f 100644
--- a/hardware/arduino/sam/cores/arduino/Arduino.h
+++ b/hardware/arduino/sam/cores/arduino/Arduino.h
@@ -209,10 +209,14 @@ extern const PinDescription g_APinDescription[] ;
 #include "watchdog.h"
 
 // USB Device
+#ifndef USB_VID
 #define USB_VID            0x2341 // arduino LLC vid
+#endif
+
 #define USB_PID_LEONARDO   0x0034
 #define USB_PID_MICRO      0x0035
 #define USB_PID_DUE        0x003E
+
 #include "USB/USBDesc.h"
 #include "USB/USBCore.h"
 #include "USB/USBAPI.h"