diff --git a/src/th-data/Sidekick_th_data.ml b/src/th-data/Sidekick_th_data.ml
index 900d1bef..d92a6d44 100644
--- a/src/th-data/Sidekick_th_data.ml
+++ b/src/th-data/Sidekick_th_data.ml
@@ -170,7 +170,6 @@ module Make(A : ARG) : S with module A = A = struct
         Expl.mk_list [
           Expl.mk_merge n1 c1.c_n;
           Expl.mk_merge n2 c2.c_n;
-          Expl.mk_merge n1 n2;
         ]
       in
       if A.Cstor.equal c1.c_cstor c2.c_cstor then (