diff --git a/matlab/TCV/gdat_tcv.m b/matlab/TCV/gdat_tcv.m
index b4ea798d249a6aa89b3b64754fd7f9cbf2328955..8a7af130963d50f5249782c9079633e1df414f3c 100644
--- a/matlab/TCV/gdat_tcv.m
+++ b/matlab/TCV/gdat_tcv.m
@@ -342,7 +342,7 @@ 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" )';