diff --git a/Makefile.am b/Makefile.am
index 5c954d6..39fca9b 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -1,6 +1,8 @@
 #
 #  Copyright © 2003 Keith Packard, Noah Levitt
 #
+#  SPDX-License-Identifier: HPND-sell-variant
+#
 #  Permission to use, copy, modify, distribute, and sell this software and its
 #  documentation for any purpose is hereby granted without fee, provided that
 #  the above copyright notice appear in all copies and that both that
diff --git a/configure.ac b/configure.ac
index 8eda92a..96e7955 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,6 +1,8 @@
 #
 #  Copyright © 2003 Keith Packard
 #
+#  SPDX-License-Identifier: HPND-sell-variant
+#
 #  Permission to use, copy, modify, distribute, and sell this software and its
 #  documentation for any purpose is hereby granted without fee, provided that
 #  the above copyright notice appear in all copies and that both that
diff --git a/include/X11/Xcursor/Xcursor.h.in b/include/X11/Xcursor/Xcursor.h.in
index a499957..c878756 100644
--- a/include/X11/Xcursor/Xcursor.h.in
+++ b/include/X11/Xcursor/Xcursor.h.in
@@ -2,6 +2,8 @@
  * Copyright © 2024 Thomas E. Dickey
  * Copyright © 2002 Keith Packard
  *
+ * SPDX-License-Identifier: HPND-sell-variant
+ *
  * Permission to use, copy, modify, distribute, and sell this software and its
  * documentation for any purpose is hereby granted without fee, provided that
  * the above copyright notice appear in all copies and that both that
diff --git a/man/Xcursor.man b/man/Xcursor.man
index a847917..b32bd19 100644
--- a/man/Xcursor.man
+++ b/man/Xcursor.man
@@ -2,6 +2,8 @@
 .\" Copyright © 2021,2024 Thomas E. Dickey
 .\" Copyright © 2002 Keith Packard
 .\"
+.\" SPDX-License-Identifier: HPND-sell-variant
+.\"
 .\" Permission to use, copy, modify, distribute, and sell this software and
 .\" its documentation for any purpose is hereby granted without fee, provided
 .\" that the above copyright notice appear in all copies and that both that
diff --git a/src/cursor.c b/src/cursor.c
index 905223c..c0ae0ea 100644
--- a/src/cursor.c
+++ b/src/cursor.c
@@ -2,6 +2,8 @@
  * Copyright © 2024 Thomas E. Dickey
  * Copyright © 2002 Keith Packard
  *
+ * SPDX-License-Identifier: HPND-sell-variant
+ *
  * Permission to use, copy, modify, distribute, and sell this software and its
  * documentation for any purpose is hereby granted without fee, provided that
  * the above copyright notice appear in all copies and that both that
diff --git a/src/display.c b/src/display.c
index a542a51..5930e01 100644
--- a/src/display.c
+++ b/src/display.c
@@ -2,6 +2,8 @@
  * Copyright © 2024 Thomas E. Dickey
  * Copyright © 2002 Keith Packard
  *
+ * SPDX-License-Identifier: HPND-sell-variant
+ *
  * Permission to use, copy, modify, distribute, and sell this software and its
  * documentation for any purpose is hereby granted without fee, provided that
  * the above copyright notice appear in all copies and that both that
diff --git a/src/file.c b/src/file.c
index 8ffb341..0347f35 100644
--- a/src/file.c
+++ b/src/file.c
@@ -2,6 +2,8 @@
  * Copyright © 2024 Thomas E. Dickey
  * Copyright © 2002 Keith Packard
  *
+ * SPDX-License-Identifier: HPND-sell-variant
+ *
  * Permission to use, copy, modify, distribute, and sell this software and its
  * documentation for any purpose is hereby granted without fee, provided that
  * the above copyright notice appear in all copies and that both that
diff --git a/src/library.c b/src/library.c
index 85c5006..35b25e8 100644
--- a/src/library.c
+++ b/src/library.c
@@ -2,6 +2,8 @@
  * Copyright © 2024 Thomas E. Dickey
  * Copyright © 2002 Keith Packard
  *
+ * SPDX-License-Identifier: HPND-sell-variant
+ *
  * Permission to use, copy, modify, distribute, and sell this software and its
  * documentation for any purpose is hereby granted without fee, provided that
  * the above copyright notice appear in all copies and that both that
diff --git a/src/xcursorint.h b/src/xcursorint.h
index 5fca76e..17dd50f 100644
--- a/src/xcursorint.h
+++ b/src/xcursorint.h
@@ -2,6 +2,8 @@
  * Copyright © 2024 Thomas E. Dickey
  * Copyright © 2002 Keith Packard
  *
+ * SPDX-License-Identifier: HPND-sell-variant
+ *
  * Permission to use, copy, modify, distribute, and sell this software and its
  * documentation for any purpose is hereby granted without fee, provided that
  * the above copyright notice appear in all copies and that both that
diff --git a/src/xlib.c b/src/xlib.c
index 79a31f3..2375a9c 100644
--- a/src/xlib.c
+++ b/src/xlib.c
@@ -2,6 +2,8 @@
  * Copyright © 2024 Thomas E. Dickey
  * Copyright © 2002 Keith Packard
  *
+ * SPDX-License-Identifier: HPND-sell-variant
+ *
  * Permission to use, copy, modify, distribute, and sell this software and its
  * documentation for any purpose is hereby granted without fee, provided that
  * the above copyright notice appear in all copies and that both that