diff --git a/BGL/include/CGAL/boost/graph/Graph_with_descriptor_with_graph_fwd.h b/BGL/include/CGAL/boost/graph/Graph_with_descriptor_with_graph_fwd.h
index 1f698a906f6..257dbf4ee46 100644
--- a/BGL/include/CGAL/boost/graph/Graph_with_descriptor_with_graph_fwd.h
+++ b/BGL/include/CGAL/boost/graph/Graph_with_descriptor_with_graph_fwd.h
@@ -13,7 +13,7 @@
 //
 // $URL$
 // $Id$
-//
+// SPDX-License-Identifier: LGPL-3.0+
 //
 // Author(s)     : Laurent Rineau
 
diff --git a/Mesh_3/include/CGAL/Mesh_error_code.h b/Mesh_3/include/CGAL/Mesh_error_code.h
index f6beccc261b..adecf884aad 100644
--- a/Mesh_3/include/CGAL/Mesh_error_code.h
+++ b/Mesh_3/include/CGAL/Mesh_error_code.h
@@ -14,6 +14,9 @@
 //
 // $URL$
 // $Id$
+// SPDX-License-Identifier: GPL-3.0+
+//
+// Author(s)     : Laurent Rineau
 
 #ifndef CGAL_MESH_ERROR_CODE_H
 #define CGAL_MESH_ERROR_CODE_H
diff --git a/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Advancing_front_mesher.h b/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Advancing_front_mesher.h
index 1adbc67ec45..98a033c6cb5 100644
--- a/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Advancing_front_mesher.h
+++ b/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Advancing_front_mesher.h
@@ -13,6 +13,8 @@
 //You should have received a copy of the GNU General Public License
 //along with this program.  If not, see <http://www.gnu.org/licenses/>.
 //
+// SPDX-License-Identifier: GPL-3.0+
+//
 // Author(s):      Simon Giraudot
 
 
diff --git a/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Alpha_shape_mesher.h b/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Alpha_shape_mesher.h
index 12d5eff474b..760c3c37b5b 100644
--- a/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Alpha_shape_mesher.h
+++ b/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Alpha_shape_mesher.h
@@ -14,6 +14,8 @@
 //You should have received a copy of the GNU General Public License
 //along with this program.  If not, see <http://www.gnu.org/licenses/>.
 //
+// SPDX-License-Identifier: GPL-3.0+
+//
 // Author(s):      Thijs van Lankveld, Simon Giraudot
 
 
diff --git a/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Jet_smoother.h b/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Jet_smoother.h
index af1546b5f35..2d7ed40ea38 100644
--- a/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Jet_smoother.h
+++ b/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Jet_smoother.h
@@ -13,6 +13,8 @@
 //You should have received a copy of the GNU General Public License
 //along with this program.  If not, see <http://www.gnu.org/licenses/>.
 //
+// SPDX-License-Identifier: GPL-3.0+
+//
 // Author(s):      Simon Giraudot
 
 
diff --git a/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Shape_construction_3.h b/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Shape_construction_3.h
index 8db9fcef667..f02d0d76aec 100644
--- a/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Shape_construction_3.h
+++ b/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Shape_construction_3.h
@@ -13,6 +13,8 @@
 //You should have received a copy of the GNU General Public License
 //along with this program.  If not, see <http://www.gnu.org/licenses/>.
 //
+// SPDX-License-Identifier: GPL-3.0+
+//
 // Author(s):      Thijs van Lankveld
 
 
diff --git a/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Weighted_PCA_smoother.h b/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Weighted_PCA_smoother.h
index d3aacdad94f..aae4f3ea184 100644
--- a/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Weighted_PCA_smoother.h
+++ b/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/Weighted_PCA_smoother.h
@@ -14,6 +14,8 @@
 //You should have received a copy of the GNU General Public License
 //along with this program.  If not, see <http://www.gnu.org/licenses/>.
 //
+// SPDX-License-Identifier: GPL-3.0+
+//
 // Author(s):      Thijs van Lankveld, Simon Giraudot
 
 
diff --git a/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/internal/Auto_count.h b/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/internal/Auto_count.h
index 2086b337c9c..b94cba97162 100644
--- a/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/internal/Auto_count.h
+++ b/Scale_space_reconstruction_3/include/CGAL/Scale_space_reconstruction_3/internal/Auto_count.h
@@ -14,6 +14,8 @@
 //You should have received a copy of the GNU General Public License
 //along with this program.  If not, see <http://www.gnu.org/licenses/>.
 //
+// SPDX-License-Identifier: GPL-3.0+
+//
 // Author(s):      Thijs van Lankveld
 
 
diff --git a/Scale_space_reconstruction_3/include/CGAL/Scale_space_surface_reconstruction_3.h b/Scale_space_reconstruction_3/include/CGAL/Scale_space_surface_reconstruction_3.h
index 0b756dc340d..942f546401b 100644
--- a/Scale_space_reconstruction_3/include/CGAL/Scale_space_surface_reconstruction_3.h
+++ b/Scale_space_reconstruction_3/include/CGAL/Scale_space_surface_reconstruction_3.h
@@ -14,6 +14,8 @@
 //You should have received a copy of the GNU General Public License
 //along with this program.  If not, see <http://www.gnu.org/licenses/>.
 //
+// SPDX-License-Identifier: GPL-3.0+
+//
 // Author(s):      Thijs van Lankveld, Simon Giraudot