diff --git a/passes/hierarchy/clkpart.cc b/passes/hierarchy/clkpart.cc
index 15a5328b9..81983e226 100644
--- a/passes/hierarchy/clkpart.cc
+++ b/passes/hierarchy/clkpart.cc
@@ -278,7 +278,7 @@ struct ClkPartPass : public Pass {
 			}
 		}
 
-		Pass::call(design, "submod");
+		Pass::call(design, "submod -hidden");
 
 		if (!attr_name.empty())
 			for (auto m : new_submods)