diff --git a/.clang-format b/.clang-format
index 30e883db..7c1a7d76 100644
--- a/.clang-format
+++ b/.clang-format
@@ -1,3 +1,5 @@
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright (c) Contributors to the OpenEXR Project.
 ---
 Language:        Cpp
 # BasedOnStyle:  LLVM
diff --git a/.git-blame-ignore-revs b/.git-blame-ignore-revs
index b2ad8d3f..8a625f5d 100644
--- a/.git-blame-ignore-revs
+++ b/.git-blame-ignore-revs
@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright (c) Contributors to the OpenEXR Project.
+
 # if you have git newer than 2.23, you can either
 # specify this on the command line
 # git blame foo.cpp --ignore-revs-file path/to/this/file
diff --git a/.gitignore b/.gitignore
index 0f0bab0c..a36992cf 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright (c) Contributors to the OpenEXR Project.
+
 build/
 _build/
 _install/
diff --git a/CHANGES.md b/CHANGES.md
index fc47b69c..91d1803a 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -1,3 +1,6 @@
+<!-- SPDX-License-Identifier: BSD-3-Clause -->
+<!-- Copyright (c) Contributors to the OpenEXR Project -->
+
 # Imath Release Notes
 
 * [Version 3.1.9](#version-319-May-31-2023) May 31, 2023
diff --git a/CODE_OF_CONDUCT.md b/CODE_OF_CONDUCT.md
index 3501232b..ff561298 100644
--- a/CODE_OF_CONDUCT.md
+++ b/CODE_OF_CONDUCT.md
@@ -1,3 +1,6 @@
+<!-- SPDX-License-Identifier: BSD-3-Clause -->
+<!-- Copyright (c) Contributors to the OpenEXR Project -->
+
 # Code of Conduct
 
 Imath is a sub-project of the OpenEXR project, which abides by Linux
diff --git a/share/ci/scripts/linux/install_boost.sh b/share/ci/scripts/linux/install_boost.sh
index 471ecffb..e194e3b1 100755
--- a/share/ci/scripts/linux/install_boost.sh
+++ b/share/ci/scripts/linux/install_boost.sh
@@ -1,5 +1,8 @@
 #!/usr/bin/env bash
 
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright (c) Contributors to the OpenEXR Project.
+
 set -ex
 
 BOOST_VERSION="$1"
diff --git a/share/ci/scripts/linux/install_cmake.sh b/share/ci/scripts/linux/install_cmake.sh
index 7f194ed3..ab796d02 100755
--- a/share/ci/scripts/linux/install_cmake.sh
+++ b/share/ci/scripts/linux/install_cmake.sh
@@ -1,5 +1,8 @@
 #!/usr/bin/env bash
 
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright (c) Contributors to the OpenEXR Project.
+
 set -ex
 
 echo "Updating to newer cmake to enable python-3"
diff --git a/share/ci/scripts/linux/install_gdb.sh b/share/ci/scripts/linux/install_gdb.sh
index 484b0239..16a9b4b1 100755
--- a/share/ci/scripts/linux/install_gdb.sh
+++ b/share/ci/scripts/linux/install_gdb.sh
@@ -1,5 +1,8 @@
 #!/usr/bin/env bash
 
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright (c) Contributors to the OpenEXR Project.
+
 set -ex
 
 GDB_VERSION="8.3"
diff --git a/share/ci/scripts/linux/install_six.sh b/share/ci/scripts/linux/install_six.sh
index 7d87ed3b..aa7fb32f 100755
--- a/share/ci/scripts/linux/install_six.sh
+++ b/share/ci/scripts/linux/install_six.sh
@@ -1,5 +1,8 @@
 #!/usr/bin/env bash
 
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright (c) Contributors to the OpenEXR Project.
+
 set -ex
 
 SIX_VERSION="1.12.0"
diff --git a/share/ci/scripts/linux/install_sonar.sh b/share/ci/scripts/linux/install_sonar.sh
index 8ed08615..a8779c4c 100755
--- a/share/ci/scripts/linux/install_sonar.sh
+++ b/share/ci/scripts/linux/install_sonar.sh
@@ -1,5 +1,8 @@
 #!/usr/bin/env bash
 
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright (c) Contributors to the OpenEXR Project.
+
 set -ex
 
 SONAR_VERSION="$1"
diff --git a/share/ci/scripts/linux/install_valgrind.sh b/share/ci/scripts/linux/install_valgrind.sh
index d6135fd6..7006a3a8 100755
--- a/share/ci/scripts/linux/install_valgrind.sh
+++ b/share/ci/scripts/linux/install_valgrind.sh
@@ -1,5 +1,8 @@
 #!/usr/bin/env bash
 
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright (c) Contributors to the OpenEXR Project.
+
 set -ex
 
 VALGRIND_VERSION="3.15.0"
diff --git a/share/ci/scripts/linux/log_valgrind.sh b/share/ci/scripts/linux/log_valgrind.sh
index 39183ba2..9153c95c 100755
--- a/share/ci/scripts/linux/log_valgrind.sh
+++ b/share/ci/scripts/linux/log_valgrind.sh
@@ -1,5 +1,8 @@
 #!/usr/bin/env bash
 
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright (c) Contributors to the OpenEXR Project.
+
 set -ex
 
 LOGDIR="$1"
diff --git a/share/ci/scripts/linux/run_gcov.sh b/share/ci/scripts/linux/run_gcov.sh
index 35ce32fe..46536690 100755
--- a/share/ci/scripts/linux/run_gcov.sh
+++ b/share/ci/scripts/linux/run_gcov.sh
@@ -3,6 +3,9 @@
 # SPDX-License-Identifier: BSD-3-Clause
 # Copyright (c) Contributors to the OpenEXR Project.
 
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright (c) Contributors to the OpenEXR Project.
+
 set -ex
 
 if [ $# -gt 0 ]
diff --git a/share/ci/scripts/macos/install_python.sh b/share/ci/scripts/macos/install_python.sh
index ab2b7092..4f27e64a 100755
--- a/share/ci/scripts/macos/install_python.sh
+++ b/share/ci/scripts/macos/install_python.sh
@@ -1,5 +1,8 @@
 #!/usr/bin/env bash
 
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright (c) Contributors to the OpenEXR Project.
+
 set -ex
 
 PYTHON_VERSION="$1"
diff --git a/share/ci/scripts/windows/install_boost.ps1 b/share/ci/scripts/windows/install_boost.ps1
index 087c06f4..ef11c84d 100755
--- a/share/ci/scripts/windows/install_boost.ps1
+++ b/share/ci/scripts/windows/install_boost.ps1
@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright (c) Contributors to the OpenEXR Project.
+
 #
 # TODO: fix this script to work with sourceforge archive!
 #
diff --git a/share/ci/scripts/windows/install_cmake.ps1 b/share/ci/scripts/windows/install_cmake.ps1
index 92cb6d61..6a47ffe8 100755
--- a/share/ci/scripts/windows/install_cmake.ps1
+++ b/share/ci/scripts/windows/install_cmake.ps1
@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright (c) Contributors to the OpenEXR Project.
+
 $cmakeVersion = $Args[0]
 $cmakeMajorMinor = [io.path]::GetFileNameWithoutExtension("$cmakeVersion")
 
diff --git a/share/ci/scripts/windows/install_python.ps1 b/share/ci/scripts/windows/install_python.ps1
index 24cb0e9f..6456b345 100755
--- a/share/ci/scripts/windows/install_python.ps1
+++ b/share/ci/scripts/windows/install_python.ps1
@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright (c) Contributors to the OpenEXR Project.
+
 $homeDir = (pwd)
 
 $pythonVersion = $Args[0]
diff --git a/src/python/PyImathTest/testStringTable.h b/src/python/PyImathTest/testStringTable.h
index 1ef13a53..311a12d4 100644
--- a/src/python/PyImathTest/testStringTable.h
+++ b/src/python/PyImathTest/testStringTable.h
@@ -1,2 +1,7 @@
+//
+// SPDX-License-Identifier: BSD-3-Clause
+// Copyright Contributors to the OpenEXR Project.
+//
+
 void testStringTable();
 
diff --git a/website/fixmanpages.sh b/website/fixmanpages.sh
index 0036179b..8bc2b3fb 100755
--- a/website/fixmanpages.sh
+++ b/website/fixmanpages.sh
@@ -1,6 +1,9 @@
 #!/bin/bash
 
-# Fix the names of doxygen-generated man page files:
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright (c) Contributors to the OpenEXR Project.
+
+# Fix the names of doxygen-generated man page Files:
 # * Strip "_ Vec" and "_ T _ _" from "Imath_Box_ Vec2_ T _ _.3"
 # * and rename "Imath_*" to "Imath::*"
 
diff --git a/website/requirements.txt b/website/requirements.txt
index d030b3b5..8bf5179d 100644
--- a/website/requirements.txt
+++ b/website/requirements.txt
@@ -1,3 +1,6 @@
+# SPDX-License-Identifier: BSD-3-Clause
+# Copyright (c) Contributors to the OpenEXR Project.
+
 sphinx == 4.4.0
 breathe
 sphinx-press-theme