Index: src_plugins/export_stl/stl_models.c
===================================================================
--- src_plugins/export_stl/stl_models.c	(revision 37343)
+++ src_plugins/export_stl/stl_models.c	(revision 37344)
@@ -247,6 +247,8 @@
 	PCB_SUBC_LOOP(PCB->Data); {
 		int good = 0;
 
+		if (subc->extobj != NULL) continue;
+
 		if (stl_model_print(pcb, outf, maxy, z0, z1, &models, subc, &first, fmt, fmt) != 0) {
 			const stl_fmt_t **n; /* fallback: try all other formats */
 			for(n = fmt_all; *n != NULL; n++) {