diff --git a/contrib/scripts/checkpatch.pl b/contrib/scripts/checkpatch.pl
index e82000302a..045d786c3a 100755
--- a/contrib/scripts/checkpatch.pl
+++ b/contrib/scripts/checkpatch.pl
@@ -205,6 +205,7 @@ complain ("Avoid g_clear_pointer() and use nm_clear_pointer() (or nm_clear_g_fre
 complain ("Define setting properties with _nm_setting_property_define_direct_*() API") if $line =~ /g_param_spec_/ and $filename =~ /\/libnm-core-impl\/nm-setting/;
 complain ("Use nm_g_array_{index,first,last,index_p}() instead of g_array_index(), as it nm_assert()s for valid element size and out-of-bound access") if $line =~ /\bg_array_index\b/;
 complain ("Use spaces instead of tabs") if $line =~ /\t/;
+complain ("Prefer implementing private pointers via _NM_GET_PRIVATE() or _NM_GET_PRIVATE_PTR() (the latter, if the private data has an opqaue pointer in the header file)") if $line =~ /\b(g_type_class_add_private|G_TYPE_INSTANCE_GET_PRIVATE)\b/;
 
 # Further on we process stuff without comments.
 $_ = $line;