diff --git a/lib/Makefile.am b/lib/Makefile.am
index f0cd3cc3..1b08d93a 100644
--- a/lib/Makefile.am
+++ b/lib/Makefile.am
@@ -43,6 +43,7 @@ libethercat_la_SOURCES = \
 
 noinst_HEADERS = \
 	domain.h \
+	ioctl.h \
 	master.h \
 	reg_request.h \
 	sdo_request.h \