diff --git a/portal/Makefile.am.inc b/portal/Makefile.am.inc
index 38a56bb1..25f56bbc 100644
--- a/portal/Makefile.am.inc
+++ b/portal/Makefile.am.inc
@@ -8,7 +8,7 @@ systemduserunit_DATA += portal/flatpak-portal.service
 service_in_files += portal/org.freedesktop.portal.Flatpak.service.in
 dbus_service_DATA += portal/org.freedesktop.portal.Flatpak.service
 
-portal_built_sources = portal/flatpak-portal-dbus.c portal/flatpak-portal-dbus.h
+nodist_flatpak_portal_SOURCES = portal/flatpak-portal-dbus.c portal/flatpak-portal-dbus.h
 
 portal/flatpak-portal-dbus.c: data/org.freedesktop.portal.Flatpak.xml Makefile
 	mkdir -p $(builddir)/portal
@@ -23,7 +23,6 @@ portal/%-dbus.h: portal/%-dbus.c
 	@true # Built as a side-effect of the rules for the .c
 
 flatpak_portal_SOURCES = \
-	$(portal_built_sources)		\
 	portal/flatpak-portal.c		\
 	portal/flatpak-portal.h		\
 	portal/flatpak-portal-app-info.c		\
@@ -32,8 +31,8 @@ flatpak_portal_SOURCES = \
 	common/flatpak-portal-error.h	\
 	$(NULL)
 
-BUILT_SOURCES += $(portal_built_sources)
-CLEANFILES += $(portal_built_sources)
+BUILT_SOURCES += $(nodist_flatpak_portal_SOURCES)
+CLEANFILES += $(nodist_flatpak_portal_SOURCES)
 
 flatpak_portal_LDADD = $(AM_LDADD) $(BASE_LIBS)
 flatpak_portal_CFLAGS = $(AM_CFLAGS) $(BASE_CFLAGS)