diff --git a/ortools/linear_solver/xpress_interface.cc b/ortools/linear_solver/xpress_interface.cc
index 3dcc8c86dc..db8bd9a713 100644
--- a/ortools/linear_solver/xpress_interface.cc
+++ b/ortools/linear_solver/xpress_interface.cc
@@ -1,4 +1,4 @@
-// Copyright 2019 RTE
+// Copyright 2019-2023 RTE
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
diff --git a/ortools/xpress/environment.cc b/ortools/xpress/environment.cc
index f91f9cdfba..924897e085 100644
--- a/ortools/xpress/environment.cc
+++ b/ortools/xpress/environment.cc
@@ -1,4 +1,4 @@
-// Copyright 2010-2021 Google LLC
+// Copyright 2019-2023 RTE
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
@@ -11,6 +11,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// Initial version of this code was provided by RTE
+
 #include "ortools/xpress/environment.h"
 
 #include <filesystem>
diff --git a/ortools/xpress/environment.h b/ortools/xpress/environment.h
index 6737a03e50..3ac9e74fb8 100644
--- a/ortools/xpress/environment.h
+++ b/ortools/xpress/environment.h
@@ -1,4 +1,4 @@
-// Copyright 2010-2021 Google LLC
+// Copyright 2019-2023 RTE
 // Licensed under the Apache License, Version 2.0 (the "License");
 // you may not use this file except in compliance with the License.
 // You may obtain a copy of the License at
@@ -11,6 +11,8 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+// Initial version of this code was provided by RTE
+
 #ifndef OR_TOOLS_XPRESS_ENVIRONMENT_H
 #define OR_TOOLS_XPRESS_ENVIRONMENT_H