diff --git a/src/math/lp/nla_basics_lemmas.cpp b/src/math/lp/nla_basics_lemmas.cpp
index 7124fd409..191e59a79 100644
--- a/src/math/lp/nla_basics_lemmas.cpp
+++ b/src/math/lp/nla_basics_lemmas.cpp
@@ -104,7 +104,7 @@ bool basics::basic_sign_lemma_model_based() {
                 return true;
         }
     }
-    return c().m_lemma_vec->size() > 0;
+    return c().m_lemmas.size() > 0;
 }
 
     
diff --git a/src/math/lp/nla_core.cpp b/src/math/lp/nla_core.cpp
index 84367fbbc..365f81774 100644
--- a/src/math/lp/nla_core.cpp
+++ b/src/math/lp/nla_core.cpp
@@ -829,7 +829,7 @@ void core::print_stats(std::ostream& out) {
         
 
 void core::clear() {
-    m_lemma_vec->clear();
+    m_lemmas.clear();
     m_literal_vec->clear();
 }
     
@@ -1066,7 +1066,7 @@ rational core::val(const factorization& f) const {
 }
 
 new_lemma::new_lemma(core& c, char const* name):name(name), c(c) {
-    c.m_lemma_vec->push_back(lemma());
+    c.m_lemmas.push_back(lemma());
 }
 
 new_lemma& new_lemma::operator|=(ineq const& ineq) {
@@ -1096,7 +1096,7 @@ new_lemma::~new_lemma() {
 }
 
 lemma& new_lemma::current() const {
-    return c.m_lemma_vec->back();
+    return c.m_lemmas.back();
 }
 
 new_lemma& new_lemma::operator&=(lp::explanation const& e) {
@@ -1209,7 +1209,7 @@ void core::negate_relation(new_lemma& lemma, unsigned j, const rational& a) {
 }
 
 bool core::conflict_found() const {
-    for (const auto & l : * m_lemma_vec) {
+    for (const auto & l : m_lemmas) {
         if (l.is_conflict())
             return true;
     }
@@ -1217,7 +1217,7 @@ bool core::conflict_found() const {
 }
 
 bool core::done() const {
-    return m_lemma_vec->size() >= 10 || 
+    return m_lemmas.size() >= 10 || 
         conflict_found() || 
         lp_settings().get_cancel_flag();
 }
@@ -1506,7 +1506,7 @@ void core::check_weighted(unsigned sz, std::pair<unsigned, std::function<void(vo
     for (unsigned i = 0; i < sz; ++i) 
         bound += checks[i].first;
     uint_set seen;
-    while (bound > 0 && !done() && m_lemma_vec->empty()) {
+    while (bound > 0 && !done() && m_lemmas.empty()) {
         unsigned n = random() % bound;
         for (unsigned i = 0; i < sz; ++i) {
             if (seen.contains(i))
@@ -1522,13 +1522,13 @@ void core::check_weighted(unsigned sz, std::pair<unsigned, std::function<void(vo
     }
 }
 
-lbool core::check_power(lpvar r, lpvar x, lpvar y, vector<lemma>& l_vec) {
-    m_lemma_vec =  &l_vec;
-    return m_powers.check(r, x, y, l_vec);
+lbool core::check_power(lpvar r, lpvar x, lpvar y) {
+    m_lemmas.reset();
+    return m_powers.check(r, x, y, m_lemmas);
 }
 
-void core::check_bounded_divisions(vector<lemma>& l_vec) {
-    m_lemma_vec = &l_vec;
+void core::check_bounded_divisions() {
+    m_lemmas.reset();
     m_divisions.check_bounded_divisions();
 }
 // looking for a free variable inside of a monic to split
@@ -1547,11 +1547,10 @@ void core::add_bounds() {
     }    
 }
 
-lbool core::check(vector<ineq>& lits, vector<lemma>& l_vec) {
+lbool core::check(vector<ineq>& lits) {
     lp_settings().stats().m_nla_calls++;
     TRACE("nla_solver", tout << "calls = " << lp_settings().stats().m_nla_calls << "\n";);
     lra.get_rid_of_inf_eps();
-    m_lemma_vec =  &l_vec;
     m_literal_vec = &lits;
     if (!(lra.get_status() == lp::lp_status::OPTIMAL || 
           lra.get_status() == lp::lp_status::FEASIBLE)) {
@@ -1572,7 +1571,7 @@ lbool core::check(vector<ineq>& lits, vector<lemma>& l_vec) {
     bool run_bounded_nlsat = should_run_bounded_nlsat();
     bool run_bounds = params().arith_nl_branching();    
 
-    auto no_effect = [&]() { return !done() && l_vec.empty() && lits.empty(); };
+    auto no_effect = [&]() { return !done() && m_lemmas.empty() && lits.empty(); };
     
     if (no_effect())
         m_monomial_bounds.propagate();
@@ -1590,7 +1589,7 @@ lbool core::check(vector<ineq>& lits, vector<lemma>& l_vec) {
               {1, check2},
               {1, check3} };
         check_weighted(3, checks);
-        if (!l_vec.empty() || !lits.empty())
+        if (!m_lemmas.empty() || !lits.empty())
             return l_false;
     }
                 
@@ -1627,15 +1626,15 @@ lbool core::check(vector<ineq>& lits, vector<lemma>& l_vec) {
         m_stats.m_nra_calls++;
     }
     
-    if (ret == l_undef && !l_vec.empty() && m_reslim.inc()) 
+    if (ret == l_undef && !m_lemmas.empty() && m_reslim.inc()) 
         ret = l_false;
 
-    m_stats.m_nla_lemmas += l_vec.size();
-    for (const auto& l : l_vec)
+    m_stats.m_nla_lemmas += m_lemmas.size();
+    for (const auto& l : m_lemmas)
         m_stats.m_nla_explanations += static_cast<unsigned>(l.expl().size());
 
     
-    TRACE("nla_solver", tout << "ret = " << ret << ", lemmas count = " << l_vec.size() << "\n";);
+    TRACE("nla_solver", tout << "ret = " << ret << ", lemmas count = " << m_lemmas.size() << "\n";);
     IF_VERBOSE(2, if(ret == l_undef) {verbose_stream() << "Monomials\n"; print_monics(verbose_stream());});
     CTRACE("nla_solver", ret == l_undef, tout << "Monomials\n"; print_monics(tout););
     return ret;
@@ -1670,13 +1669,13 @@ lbool core::bounded_nlsat() {
         m_nlsat_delay /= 2;
     }
     if (ret == l_true) {
-        m_lemma_vec->reset();
+        m_lemmas.reset();
     }
     return ret;
 }
 
 bool core::no_lemmas_hold() const {
-    for (auto & l : * m_lemma_vec) {
+    for (auto & l : m_lemmas) {
         if (lemma_holds(l)) {
             TRACE("nla_solver", print_lemma(l, tout););
             return false;
@@ -1685,10 +1684,10 @@ bool core::no_lemmas_hold() const {
     return true;
 }
     
-lbool core::test_check(vector<lemma>& l) {
+lbool core::test_check() {
     vector<ineq> lits;
     lra.set_status(lp::lp_status::OPTIMAL);
-    return check(lits, l);
+    return check(lits);
 }
 
 std::ostream& core::print_terms(std::ostream& out) const {
@@ -2027,12 +2026,12 @@ void core::add_lower_bound_monic(lpvar j, const lp::mpq& v, bool is_strict, std:
         }
     }
 
-    void core::init_bound_propagation(vector<nla::lemma>& lemma_vector) {
+    void core::init_bound_propagation() {
         m_implied_bounds.clear();
         m_improved_lower_bounds.reset();
         m_improved_upper_bounds.reset();
         m_column_types = &lra.get_column_types();
-        lemma_vector.clear();
+        m_lemmas.clear();
     }
 
 }  // namespace nla
diff --git a/src/math/lp/nla_core.h b/src/math/lp/nla_core.h
index c561b91c0..90bfa18ca 100644
--- a/src/math/lp/nla_core.h
+++ b/src/math/lp/nla_core.h
@@ -85,7 +85,7 @@ class core {
     reslimit&                m_reslim;
     smt_params_helper        m_params;
     std::function<bool(lpvar)> m_relevant;
-    vector<lemma> *          m_lemma_vec;
+    vector<lemma>            m_lemmas;
     vector<ineq> *           m_literal_vec = nullptr;
     indexed_uint_set         m_to_refine;
     vector<lpvar>            m_monics_with_changed_bounds;
@@ -393,15 +393,15 @@ public:
 
     bool  conflict_found() const;
     
-    lbool check(vector<ineq>& ineqs, vector<lemma>& l_vec);
-    lbool check_power(lpvar r, lpvar x, lpvar y, vector<lemma>& l_vec);
-    void check_bounded_divisions(vector<lemma>&);
+    lbool check(vector<ineq>& ineqs);
+    lbool check_power(lpvar r, lpvar x, lpvar y);
+    void check_bounded_divisions();
 
     bool  no_lemmas_hold() const;
 
-    void propagate(vector<lemma>& lemmas);
+    // void propagate();
     
-    lbool  test_check(vector<lemma>& l);
+    lbool  test_check();
     lpvar map_to_root(lpvar) const;
     std::ostream& print_terms(std::ostream&) const;
     std::ostream& print_term(const lp::lar_term&, std::ostream&) const;
@@ -443,6 +443,8 @@ public:
     void add_upper_bound_monic(lpvar j, const lp::mpq& v, bool is_strict, std::function<u_dependency*()> explain_dep);    
     bool upper_bound_is_available(unsigned j) const;
     bool lower_bound_is_available(unsigned j) const;
+    vector<nla::lemma> const& lemmas() const { return m_lemmas; }        
+
 private:
     lp::column_type get_column_type(unsigned j) const { return (*m_column_types)[j]; }
     void constrain_nl_in_tableau();
@@ -451,7 +453,7 @@ private:
     void save_tableau();
     bool integrality_holds();
     void calculate_implied_bounds_for_monic(lp::lpvar v);
-    void init_bound_propagation(vector<nla::lemma> &);    
+    void init_bound_propagation();    
 };  // end of core
 
 struct pp_mon {
diff --git a/src/math/lp/nla_solver.cpp b/src/math/lp/nla_solver.cpp
index e8b2d9d1d..b16d14021 100644
--- a/src/math/lp/nla_solver.cpp
+++ b/src/math/lp/nla_solver.cpp
@@ -42,8 +42,8 @@ namespace nla {
     
     bool solver::need_check() { return m_core->has_relevant_monomial(); }
     
-    lbool solver::check(vector<ineq>& lits, vector<lemma>& lemmas) {
-        return m_core->check(lits, lemmas);
+    lbool solver::check(vector<ineq>& lits) {
+        return m_core->check(lits);
     }
 
     void solver::push(){
@@ -92,16 +92,20 @@ namespace nla {
         m_core->calculate_implied_bounds_for_monic(v);
     }
     // ensure r = x^y, add abstraction/refinement lemmas
-    lbool solver::check_power(lpvar r, lpvar x, lpvar y, vector<lemma>& lemmas) {
-        return m_core->check_power(r, x, y, lemmas);
+    lbool solver::check_power(lpvar r, lpvar x, lpvar y) {
+        return m_core->check_power(r, x, y);
     }
 
-    void solver::check_bounded_divisions(vector<lemma>& lemmas) {
-        m_core->check_bounded_divisions(lemmas);
+    void solver::check_bounded_divisions() {
+        m_core->check_bounded_divisions();
     }
 
-    void solver::init_bound_propagation(vector<nla::lemma>& nla_lemma_vector) {
-        m_core->init_bound_propagation(nla_lemma_vector);
+    void solver::init_bound_propagation() {
+        m_core->init_bound_propagation();
+    }
+
+    vector<nla::lemma> const& solver::lemmas() const {
+        return m_core->lemmas();
     }
 
 }
diff --git a/src/math/lp/nla_solver.h b/src/math/lp/nla_solver.h
index 7f52b5c92..b4fba1f86 100644
--- a/src/math/lp/nla_solver.h
+++ b/src/math/lp/nla_solver.h
@@ -23,7 +23,7 @@ namespace nla {
     class solver {
         core* m_core;
     public:
-
+        
         solver(lp::lar_solver& s, params_ref const& p, reslimit& limit, std_vector<lp::implied_bound> & implied_bounds);
         ~solver();
         const auto& monics_with_changed_bounds() const { return m_core->monics_with_changed_bounds(); }
@@ -32,14 +32,14 @@ namespace nla {
         void add_idivision(lpvar q, lpvar x, lpvar y);
         void add_rdivision(lpvar q, lpvar x, lpvar y);
         void add_bounded_division(lpvar q, lpvar x, lpvar y);
-        void check_bounded_divisions(vector<lemma>&);
+        void check_bounded_divisions();
         void set_relevant(std::function<bool(lpvar)>& is_relevant);
         void push();
         void pop(unsigned scopes);
         bool need_check();
-        lbool check(vector<ineq>& lits, vector<lemma>&);
-        void propagate(vector<lemma>& lemmas);
-        lbool check_power(lpvar r, lpvar x, lpvar y, vector<lemma>&);
+        lbool check(vector<ineq>& lits);
+        void propagate();
+        lbool check_power(lpvar r, lpvar x, lpvar y);
         bool is_monic_var(lpvar) const;
         bool influences_nl_var(lpvar) const;
         std::ostream& display(std::ostream& out) const;
@@ -49,6 +49,8 @@ namespace nla {
         nlsat::anum const& am_value(lp::var_index v) const;
         void collect_statistics(::statistics & st);
         void calculate_implied_bounds_for_monic(lp::lpvar v);
-        void init_bound_propagation(vector<nla::lemma>&);
+        void init_bound_propagation();
+        vector<nla::lemma> const& lemmas() const;        
+
     };
 }
diff --git a/src/sat/smt/arith_solver.cpp b/src/sat/smt/arith_solver.cpp
index 3cf991c20..893fe4a43 100644
--- a/src/sat/smt/arith_solver.cpp
+++ b/src/sat/smt/arith_solver.cpp
@@ -1459,11 +1459,11 @@ namespace arith {
             return l_true;
 
         m_a1 = nullptr; m_a2 = nullptr;
-        lbool r = m_nla->check(m_nla_literals, m_nla_lemma_vector);
+        lbool r = m_nla->check(m_nla_literals);
         switch (r) {
         case l_false:
             assume_literals();
-            for (const nla::lemma& l : m_nla_lemma_vector)
+            for (const nla::lemma& l : m_nla->lemmas())
                 false_case_of_check_nla(l);
             break;
         case l_true:
diff --git a/src/sat/smt/arith_solver.h b/src/sat/smt/arith_solver.h
index 8917a3e42..53b49a658 100644
--- a/src/sat/smt/arith_solver.h
+++ b/src/sat/smt/arith_solver.h
@@ -249,7 +249,6 @@ namespace arith {
 
         // lemmas
         lp::explanation     m_explanation;
-        vector<nla::lemma>  m_nla_lemma_vector;
         vector<nla::ineq>   m_nla_literals;
         literal_vector      m_core, m_core2;
         vector<rational>    m_coeffs;
diff --git a/src/smt/theory_lra.cpp b/src/smt/theory_lra.cpp
index 5405f7ff1..ce53b8f25 100644
--- a/src/smt/theory_lra.cpp
+++ b/src/smt/theory_lra.cpp
@@ -1601,11 +1601,11 @@ public:
             return FC_DONE;
         if (!m_nla)
             return FC_GIVEUP;
-        switch (m_nla->check_power(get_lpvar(e), get_lpvar(x), get_lpvar(y), m_nla_lemma_vector)) {
+        switch (m_nla->check_power(get_lpvar(e), get_lpvar(x), get_lpvar(y))) {
         case l_true:
             return FC_DONE;
         case l_false:
-            for (const nla::lemma & l : m_nla_lemma_vector) 
+            for (const nla::lemma & l : m_nla->lemmas()) 
                 false_case_of_check_nla(l);
             return FC_CONTINUE;
         case l_undef:
@@ -1802,11 +1802,10 @@ public:
     bool check_idiv_bounds() {
         if (!m_nla)
             return true;
-        m_nla_lemma_vector.reset();
-        m_nla->check_bounded_divisions(m_nla_lemma_vector);
-        for (auto & lemma : m_nla_lemma_vector)
+        m_nla->check_bounded_divisions();
+        for (auto & lemma : m_nla->lemmas())
             false_case_of_check_nla(lemma);
-        return m_nla_lemma_vector.empty();         
+        return m_nla->lemmas().empty();        
     }
 
     expr_ref var2expr(lpvar v) {
@@ -2025,13 +2024,13 @@ public:
     
     final_check_status check_nla_continue() {
         m_a1 = nullptr; m_a2 = nullptr;
-        lbool r = m_nla->check(m_nla_literals, m_nla_lemma_vector);
+        lbool r = m_nla->check(m_nla_literals);
 
         switch (r) {
         case l_false:
             for (const nla::ineq& i : m_nla_literals)
                 assume_literal(i); 
-            for (const nla::lemma & l : m_nla_lemma_vector) 
+            for (const nla::lemma & l : m_nla->lemmas()) 
                 false_case_of_check_nla(l);
             return FC_CONTINUE;
         case l_true:
@@ -2201,12 +2200,12 @@ public:
     }
     
     void propagate_bounds_for_touched_monomials() {
-        m_nla->init_bound_propagation(m_nla_lemma_vector);
+        m_nla->init_bound_propagation();
         for (unsigned v : m_nla->monics_with_changed_bounds()) 
             m_nla->calculate_implied_bounds_for_monic(v);
         
         m_nla->reset_monics_with_changed_bounds();
-        for (const auto & l : m_nla_lemma_vector) 
+        for (const auto & l : m_nla->lemmas()) 
             false_case_of_check_nla(l);
     }
 
@@ -3210,7 +3209,6 @@ public:
     }
  
     lp::explanation     m_explanation;
-    vector<nla::lemma>  m_nla_lemma_vector;
     vector<nla::ineq>       m_nla_literals;
     literal_vector      m_core;
     svector<enode_pair> m_eqs;