diff --git a/sdk/include/ddk/poclass.h b/sdk/include/ddk/poclass.h
index cf5a9c84404..ab4d4f7b8fa 100644
--- a/sdk/include/ddk/poclass.h
+++ b/sdk/include/ddk/poclass.h
@@ -50,6 +50,8 @@ DEFINE_GUID(GUID_DEVICE_SYS_BUTTON,
 DEFINE_GUID(GUID_DEVICE_THERMAL_ZONE,
   0x4AFA3D51L, 0x74A7, 0x11d0, 0xbe, 0x5e, 0x00, 0xA0, 0xC9, 0x06, 0x28, 0x57);
 
+DEFINE_GUID(GUID_DEVICE_FAN,
+  0x05ecd13dL, 0x81da, 0x4a2a, 0x8a, 0x4c, 0x52, 0x4f, 0x23, 0xdd, 0x4d, 0xc9);
 
 #define IOCTL_GET_PROCESSOR_OBJ_INFO \
   CTL_CODE(FILE_DEVICE_BATTERY, 0x60, METHOD_BUFFERED, FILE_READ_ACCESS)