diff --git a/src/ackr/lackr.cpp b/src/ackr/lackr.cpp
index aa99f347e..3bbfed791 100644
--- a/src/ackr/lackr.cpp
+++ b/src/ackr/lackr.cpp
@@ -29,10 +29,10 @@
 ///////////////
 #include"model_smt2_pp.h"
 ///////////////
-lackr::lackr(ast_manager& m, params_ref p, lackr_stats& st, expr_ref _f)
+lackr::lackr(ast_manager& m, params_ref p, lackr_stats& st, expr_ref_vector& formulas)
     : m_m(m)
     , m_p(p)
-    , m_fla(m)
+    , m_formulas(formulas)
     , m_abstr(m)
     , m_sat(0)
     , m_bvutil(m)
@@ -40,7 +40,6 @@ lackr::lackr(ast_manager& m, params_ref p, lackr_stats& st, expr_ref _f)
     , m_ackrs(m) 
     , m_st(st)
 {
-    m_fla = _f;
     updt_params(p);
 }
 
@@ -135,6 +134,7 @@ void lackr::eager_enc() {
     }
 }
 
+
 void lackr::abstract() {
     const fun2terms_map::iterator e = m_fun2terms.end();
     for (fun2terms_map::iterator i = m_fun2terms.begin(); i != e; ++i) {
@@ -155,8 +155,13 @@ void lackr::abstract() {
         }
     }
     m_info->seal();
-    m_info->abstract(m_fla.get(), m_abstr);
-    TRACE("lackr", tout << "abs(\n" << mk_ismt2_pp(m_abstr.get(), m_m, 2) << ")\n";);    
+    // perform abstraction of the formulas
+    const unsigned sz = m_formulas.size();
+    for (unsigned i = 0; i < sz; ++i) {
+        expr_ref a(m_m);
+        m_info->abstract(m_formulas.get(i), a);
+        m_abstr.push_back(a);
+    }
 }
 
 void lackr::add_term(app* a) {
@@ -173,9 +178,15 @@ void lackr::add_term(app* a) {
     ts->insert(a);
 }
 
+void  lackr::push_abstraction() {
+    const unsigned sz = m_abstr.size();
+    for (unsigned i = 0; i < sz; ++i) {
+        m_sat->assert_expr(m_abstr.get(i));
+    }
+}
 
 lbool lackr::eager() {
-    m_sat->assert_expr(m_abstr);
+    push_abstraction();
     TRACE("lackr", tout << "run sat 0\n"; );
     const lbool rv0 = m_sat->check_sat(0, 0);
     if (rv0 == l_false) return l_false;    
@@ -190,7 +201,7 @@ lbool lackr::eager() {
 
 lbool lackr::lazy() {
     lackr_model_constructor mc(m_m, m_info);
-    m_sat->assert_expr(m_abstr);
+    push_abstraction();
     unsigned ackr_head = 0;    
     while (1) {
         m_st.m_it++;
@@ -237,7 +248,10 @@ void lackr::collect_terms() {
     ptr_vector<expr> stack;
     expr *           curr;
     expr_mark        visited;
-    stack.push_back(m_fla.get());
+    for(unsigned i = 0; i < m_formulas.size(); ++i) {
+        stack.push_back(m_formulas.get(i));
+    }
+
     while (!stack.empty()) {
         curr = stack.back();
         if (visited.is_marked(curr)) {
diff --git a/src/ackr/lackr.h b/src/ackr/lackr.h
index ea1ea7ce2..e0a5394ab 100644
--- a/src/ackr/lackr.h
+++ b/src/ackr/lackr.h
@@ -37,7 +37,7 @@ struct lackr_stats {
 
 class lackr {
     public:
-        lackr(ast_manager& m, params_ref p, lackr_stats& st, expr_ref _f);
+        lackr(ast_manager& m, params_ref p, lackr_stats& st, expr_ref_vector& formulas);
         ~lackr();
         void updt_params(params_ref const & _p) {
             ackr_params p(_p);
@@ -66,8 +66,8 @@ class lackr {
         typedef obj_map<func_decl, app_set*> fun2terms_map;
         ast_manager&                         m_m;
         params_ref                           m_p;
-        expr_ref                             m_fla;
-        expr_ref                             m_abstr;
+        expr_ref_vector                      m_formulas;
+        expr_ref_vector                      m_abstr;
         fun2terms_map                        m_fun2terms;
         ackr_info_ref                        m_info;
         scoped_ptr<solver>                   m_sat;
@@ -96,6 +96,8 @@ class lackr {
 
         void abstract();
 
+        void push_abstraction();
+
         void add_term(app* a);
 
         //
diff --git a/src/ackr/lackr_tactic.cpp b/src/ackr/lackr_tactic.cpp
index 27cd12415..2302e859f 100644
--- a/src/ackr/lackr_tactic.cpp
+++ b/src/ackr/lackr_tactic.cpp
@@ -48,13 +48,11 @@ public:
         mc = 0;
         ast_manager& m(g->m());
         TRACE("lackr", g->display(tout << "Goal:\n"););
-        // conflate all assertions into one conjunction
-        ptr_vector<expr> flas;
-        g->get_formulas(flas);
-        expr_ref f(m);
-        f = m.mk_and(flas.size(), flas.c_ptr());
         // running implementation
-        scoped_ptr<lackr> imp = alloc(lackr, m, m_p, m_st, f);
+        expr_ref_vector flas(m);
+        const unsigned sz = g->size();
+        for (unsigned i = 0; i < sz; i++) flas.push_back(g->form(i));
+        scoped_ptr<lackr> imp = alloc(lackr, m, m_p, m_st, flas);
         const lbool o = imp->operator()();
         flas.reset();
         // report result