diff --git a/src/math/lp/static_matrix.cpp b/src/math/lp/static_matrix.cpp
index 571e9b1d06d..cde96277b5e 100644
--- a/src/math/lp/static_matrix.cpp
+++ b/src/math/lp/static_matrix.cpp
@@ -24,7 +24,6 @@ Revision History:
 #include "math/lp/static_matrix_def.h"
 #include "math/lp/lp_core_solver_base.h"
 #include "math/lp/lp_dual_core_solver.h"
-#include "math/lp/lp_dual_simplex.h"
 #include "math/lp/lp_primal_core_solver.h"
 #include "math/lp/scaler.h"
 #include "math/lp/lar_solver.h"
diff --git a/src/sat/smt/arith_sls.h b/src/sat/smt/arith_sls.h
index af3a462340b..f5044187195 100644
--- a/src/sat/smt/arith_sls.h
+++ b/src/sat/smt/arith_sls.h
@@ -21,7 +21,6 @@ Module Name:
 #include "ast/arith_decl_plugin.h"
 #include "math/lp/lp_solver.h"
 #include "math/lp/lp_primal_simplex.h"
-#include "math/lp/lp_dual_simplex.h"
 #include "math/lp/indexed_value.h"
 #include "math/lp/lar_solver.h"
 #include "math/lp/nla_solver.h"
diff --git a/src/smt/theory_lra.cpp b/src/smt/theory_lra.cpp
index d61910ff20e..4180f9ec344 100644
--- a/src/smt/theory_lra.cpp
+++ b/src/smt/theory_lra.cpp
@@ -21,7 +21,6 @@
 #include "util/stopwatch.h"
 #include "math/lp/lp_solver.h"
 #include "math/lp/lp_primal_simplex.h"
-#include "math/lp/lp_dual_simplex.h"
 #include "math/lp/indexed_value.h"
 #include "math/lp/lar_solver.h"
 #include "math/lp/nla_solver.h"
diff --git a/src/test/lp/smt_reader.h b/src/test/lp/smt_reader.h
index ee41a418aef..6060370a810 100644
--- a/src/test/lp/smt_reader.h
+++ b/src/test/lp/smt_reader.h
@@ -24,7 +24,6 @@ Revision History:
 #include <vector>
 #include <unordered_map>
 #include "math/lp/lp_primal_simplex.h"
-#include "math/lp/lp_dual_simplex.h"
 #include "math/lp/lar_solver.h"
 #include <iostream>
 #include <fstream>