diff --git a/src/muz/rel/dl_base.cpp b/src/muz/rel/dl_base.cpp
index a00c50d9e..6eba021f1 100644
--- a/src/muz/rel/dl_base.cpp
+++ b/src/muz/rel/dl_base.cpp
@@ -518,6 +518,7 @@ namespace datalog {
             relation_manager & manager = t.get_manager();
             table_join_fn * join_fn = manager.mk_join_fn(t, t, m_group_by_cols, m_group_by_cols);
             table_base * join_table = (*join_fn)(t, t);
+            dealloc(join_fn);
 
             table_base::iterator join_table_it = join_table->begin();
             table_base::iterator join_table_end = join_table->end();
@@ -545,6 +546,8 @@ namespace datalog {
 
             table_transformer_fn * project_fn = manager.mk_project_fn(*join_table, cols);
             table_base * gt_table = (*project_fn)(*join_table);
+            dealloc(project_fn);
+            join_table->deallocate();
 
             for (unsigned k = 0; k < cols.size(); ++k) {
                 cols[k] = k;
@@ -555,6 +558,7 @@ namespace datalog {
             table_base * result = t.clone();
             table_intersection_filter_fn * diff_fn = manager.mk_filter_by_negation_fn(*result, *gt_table, cols, cols);
             (*diff_fn)(*result, *gt_table);
+            dealloc(diff_fn);
             gt_table->deallocate();
             return result;
         }
diff --git a/src/muz/rel/dl_instruction.cpp b/src/muz/rel/dl_instruction.cpp
index c903519ce..77ba387bb 100644
--- a/src/muz/rel/dl_instruction.cpp
+++ b/src/muz/rel/dl_instruction.cpp
@@ -916,6 +916,7 @@ namespace datalog {
             const relation_signature & r_sig = s.get_signature();
             table_min_fn * fn = r_manager.mk_min_fn(source_t, m_group_by_cols, m_min_col);
             table_base * target_t = (*fn)(source_t);
+            dealloc(fn);
 
             TRACE("dl",
                 tout << "% ";
diff --git a/src/muz/rel/dl_relation_manager.cpp b/src/muz/rel/dl_relation_manager.cpp
index 95b35899e..2b78baf05 100644
--- a/src/muz/rel/dl_relation_manager.cpp
+++ b/src/muz/rel/dl_relation_manager.cpp
@@ -354,7 +354,9 @@ namespace datalog {
         return product_relation_plugin::get_plugin(*this).mk_empty(s);
     }
 
-
+    /**
+      The newly created object takes ownership of the \c table object.
+    */
     relation_base * relation_manager::mk_table_relation(const relation_signature & s, table_base * table) {
         SASSERT(s.size()==table->get_signature().size());
         return get_table_relation_plugin(table->get_plugin()).mk_from_table(s, table);
diff --git a/src/muz/rel/dl_table_relation.cpp b/src/muz/rel/dl_table_relation.cpp
index 364c29367..d42d071aa 100644
--- a/src/muz/rel/dl_table_relation.cpp
+++ b/src/muz/rel/dl_table_relation.cpp
@@ -63,6 +63,9 @@ namespace datalog {
         return alloc(table_relation, *this, s, t);
     }
 
+    /**
+      The newly created object takes ownership of the \c t object.
+    */
     relation_base * table_relation_plugin::mk_from_table(const relation_signature & s, table_base * t) {
         if (&t->get_plugin() == &m_table_plugin)
             return alloc(table_relation, *this, s, t);