diff --git a/matlab/TCV/gdat_tcv.m b/matlab/TCV/gdat_tcv.m
index a6118f64c65737d25943d7f4ca4bed810cb82bea..b177db5366a348253725e2c84e30d00a73774ef1 100644
--- a/matlab/TCV/gdat_tcv.m
+++ b/matlab/TCV/gdat_tcv.m
@@ -341,7 +341,7 @@ if (iscell(mapping_for_tcv.expression) || isempty(strfind(mapping_for_tcv.expres
   % requires FBTE
   liuqe_version_eff = -1;
   liuqe_version = -1;
-  if isempty(findstr(mapping_for_tcv.expression,'tcv_eq'))
+  if isempty(findstr(mapping_for_tcv.expression,'tcv_eq')) && isempty(findstr(mapping_for_tcv.expression,'\'))
     % if tcv_eq in expression, liuqe target will be modified to FBTE below with regexprep
     begstr = 'tcv_eq( "';
     substr_liuqe = '", "FBTE" )';