diff --git a/ortools/sat/BUILD b/ortools/sat/BUILD
index 3f91427b9f..8d749bbcf7 100644
--- a/ortools/sat/BUILD
+++ b/ortools/sat/BUILD
@@ -1018,6 +1018,7 @@ cc_library(
         "//ortools/base:threadpool",
         "//ortools/util:random_engine",
         "//ortools/util:time_limit",
+        "@com_google_absl//absl/synchronization",        
     ],
 )
 
diff --git a/ortools/sat/cp_model_lns.h b/ortools/sat/cp_model_lns.h
index 7e67c14231..f1b7a9fee4 100644
--- a/ortools/sat/cp_model_lns.h
+++ b/ortools/sat/cp_model_lns.h
@@ -16,6 +16,7 @@
 
 #include <vector>
 
+#include "absl/synchronization/mutex.h"
 #include "absl/types/span.h"
 #include "ortools/base/integral_types.h"
 #include "ortools/sat/cp_model.pb.h"
diff --git a/ortools/sat/lns.h b/ortools/sat/lns.h
index 31a33bc95d..96d2a5e4bf 100644
--- a/ortools/sat/lns.h
+++ b/ortools/sat/lns.h
@@ -20,8 +20,7 @@
 #include <vector>
 
 #if !defined(__PORTABLE_PLATFORM__)
-#include "absl/synchronization/mutex.h"
-#include "ortools/base/threadpool.h"
+ #include "ortools/base/threadpool.h"
 #endif  // __PORTABLE_PLATFORM__
 
 namespace operations_research {