diff --git a/src/sat/sat_npn3_finder.cpp b/src/sat/sat_npn3_finder.cpp
index 4cc2fe8a2..1d33f9947 100644
--- a/src/sat/sat_npn3_finder.cpp
+++ b/src/sat/sat_npn3_finder.cpp
@@ -66,6 +66,7 @@ namespace sat {
         find_maj(clauses);
         find_orand(clauses);
         find_andxor(clauses);
+        find_gamble(clauses);
     }
 
     bool npn3_finder::implies(literal a, literal b) const {
@@ -299,6 +300,65 @@ namespace sat {
         find_npn3(clauses, m_on_orand, try_orand);
     }
 
+    void npn3_finder::find_gamble(clause_vector& clauses) {
+        if (!m_on_gamble) return;
+
+        binary_hash_table_t binaries;
+        ternary_hash_table_t ternaries;
+        quaternary_hash_table_t quaternaries;
+        process_more_clauses(clauses, binaries, ternaries, quaternaries);
+
+        const auto try_gamble = [&](literal w, literal x, literal y, literal z, clause &c) {
+          clause *c1, *c2, *c3, *c4;
+          if (!has_quaternary(quaternaries, ternaries, ~x, ~y, ~z, w, c1)) return false;
+          if (!has_ternary(ternaries, ~x, y, ~w, c2)) return false;
+          if (!has_ternary(ternaries, ~y, z, ~w, c3)) return false;
+          if (!has_ternary(ternaries, x, ~z, ~w, c4)) return false;
+
+          c.mark_used();
+          if (c1) c1->mark_used();
+          if (c2) c2->mark_used();
+          if (c3) c3->mark_used();
+          if (c4) c4->mark_used();
+          m_on_gamble(w, x, y, z);
+          return true;
+        };
+
+        for (clause* cp : clauses) {
+            clause& c = *cp;
+            if (c.size() != 4 || c.was_used()) continue;
+            literal w = c[0], x = c[1], y = c[2], z = c[3];
+
+            if (try_gamble(w, x, y, z, c)) continue;
+            if (try_gamble(w, x, z, y, c)) continue;
+            if (try_gamble(w, y, x, z, c)) continue;
+            if (try_gamble(w, y, z, x, c)) continue;
+            if (try_gamble(w, z, x, y, c)) continue;
+            if (try_gamble(w, z, y, x, c)) continue;
+            if (try_gamble(x, w, y, z, c)) continue;
+            if (try_gamble(x, w, z, y, c)) continue;
+            if (try_gamble(x, y, w, z, c)) continue;
+            if (try_gamble(x, y, z, w, c)) continue;
+            if (try_gamble(x, z, w, y, c)) continue;
+            if (try_gamble(x, z, y, w, c)) continue;
+            if (try_gamble(y, w, x, z, c)) continue;
+            if (try_gamble(y, w, z, x, c)) continue;
+            if (try_gamble(y, x, w, z, c)) continue;
+            if (try_gamble(y, x, z, w, c)) continue;
+            if (try_gamble(y, z, w, x, c)) continue;
+            if (try_gamble(y, z, x, w, c)) continue;
+            if (try_gamble(z, w, x, y, c)) continue;
+            if (try_gamble(z, w, y, x, c)) continue;
+            if (try_gamble(z, x, w, y, c)) continue;
+            if (try_gamble(z, x, y, w, c)) continue;
+            if (try_gamble(z, y, w, x, c)) continue;
+            if (try_gamble(z, y, x, w, c)) continue;
+        }
+
+        std::function<bool(clause*)> not_used = [](clause* cp) { return !cp->was_used(); };
+        clauses.filter_update(not_used);
+    }
+
     void npn3_finder::find_andxor(clause_vector& clauses) {
         if (!m_on_andxor) return;
 
diff --git a/src/sat/sat_npn3_finder.h b/src/sat/sat_npn3_finder.h
index cb544909f..729a9b263 100644
--- a/src/sat/sat_npn3_finder.h
+++ b/src/sat/sat_npn3_finder.h
@@ -40,6 +40,7 @@ namespace sat {
         on_function_t m_on_maj;
         on_function_t m_on_orand;
         on_function_t m_on_andxor;
+        on_function_t m_on_gamble;
 
         typedef svector<std::pair<literal, clause*>> use_list_t;
         scoped_ptr_vector<use_list_t> m_use_lists;
@@ -99,6 +100,7 @@ namespace sat {
         void find_maj(clause_vector& clauses);
         void find_orand(clause_vector& clauses);
         void find_andxor(clause_vector& clauses);
+        void find_gamble(clause_vector& clauses);
         void validate_clause(literal x, literal y, literal z, vector<literal_vector> const& clauses);
         void validate_clause(literal_vector const& clause, vector<literal_vector> const& clauses);
 
@@ -110,6 +112,7 @@ namespace sat {
         void set_on_maj(std::function<void(literal head, literal a, literal b, literal c)> const& f) { m_on_maj = f; }
         void set_on_orand(std::function<void(literal head, literal a, literal b, literal c)> const& f) { m_on_orand = f; }
         void set_on_andxor(std::function<void(literal head, literal a, literal b, literal c)> const& f) { m_on_andxor = f; }
+        void set_on_gamble(std::function<void(literal head, literal a, literal b, literal c)> const& f) { m_on_gamble = f; }
         void operator()(clause_vector& clauses);
     };
 }