diff --git a/libraries/AP_UAVCAN/AP_UAVCAN_SLCAN.cpp b/libraries/AP_UAVCAN/AP_UAVCAN_SLCAN.cpp
index e2ce98363a..6ddd8225e5 100644
--- a/libraries/AP_UAVCAN/AP_UAVCAN_SLCAN.cpp
+++ b/libraries/AP_UAVCAN/AP_UAVCAN_SLCAN.cpp
@@ -23,7 +23,6 @@
 
 #include "AP_UAVCAN_SLCAN.h"
 #include <AP_SerialManager/AP_SerialManager.h>
-#include <AP_Common/Semaphore.h>
 
 #include <AP_HAL_ChibiOS/CANSerialRouter.h>