diff --git a/modules/conop/src/compound_lib_base.cc b/modules/conop/src/compound_lib_base.cc
index 7fbb5520de05811568739c544faeb4402c976aef..5fda96f37691a21a62f7420bb21bbb7a81693cce 100644
--- a/modules/conop/src/compound_lib_base.cc
+++ b/modules/conop/src/compound_lib_base.cc
@@ -13,7 +13,7 @@ bool CompoundLibBase::IsResidueComplete(const ost::mol::ResidueHandle& res, bool
 
     if((it->element=="H" || it->element=="D") && (!check_hydrogens)) continue;
 
-    if(res.FindAtom(it->name).IsValid() || res.FindAtom(it->alt_name)) continue;
+    if(res.FindAtom(it->name).IsValid() || res.FindAtom(it->alt_name).IsValid()) continue;
 
     return false;