diff --git a/tuos-presentation/README.md b/tuos-presentation/README.md
index 3c33971..940d747 100644
--- a/tuos-presentation/README.md
+++ b/tuos-presentation/README.md
@@ -42,5 +42,5 @@ slides such as `\PartFrame{}`, `\ThanksFrame{}`, or `\CopyrightFrame`.
 
 ## License
 This project is dual-licensed under a 2-clause BSD-style license and/or 
-the LPPL version 1 or any later version. 
+the LPPL version 1.3c or (at your opinion) any later version. 
 
diff --git a/tuos-presentation/beamercolorthemetuos.sty b/tuos-presentation/beamercolorthemetuos.sty
index c097097..11db070 100644
--- a/tuos-presentation/beamercolorthemetuos.sty
+++ b/tuos-presentation/beamercolorthemetuos.sty
@@ -4,10 +4,11 @@
 %%   This program can be redistributed and/or modified under the terms
 %%   of the LaTeX Project Public License Distributed from CTAN
 %%   archives in directory macros/latex/base/lppl.txt; either
-%%   version 1 of the License, or any later version.
+%%   version 1.3c of the License, or (at your opinion) any later version.
 %%   OR
 %%   The 2-clause BSD-style license.
 %%
+%%   SPDX-License-Identifier: LPPL-1.3c+ OR BSD-2-Clause
 \NeedsTeXFormat{LaTeX2e}[1994/06/01]
 \ProvidesPackage{beamercolorthemetuos}
      [2016/08/20 v1.1  LaTeX presentation class following the cooperate design of The University of Sheffield]
diff --git a/tuos-presentation/beamerfontthemetuos.sty b/tuos-presentation/beamerfontthemetuos.sty
index a2873bf..2917309 100644
--- a/tuos-presentation/beamerfontthemetuos.sty
+++ b/tuos-presentation/beamerfontthemetuos.sty
@@ -4,10 +4,11 @@
 %%   This program can be redistributed and/or modified under the terms
 %%   of the LaTeX Project Public License Distributed from CTAN
 %%   archives in directory macros/latex/base/lppl.txt; either
-%%   version 1 of the License, or any later version.
+%%   version 1.3c of the License, or (at your opinion) any later version.
 %%   OR
 %%   The 2-clause BSD-style license.
 %%
+%%   SPDX-License-Identifier: LPPL-1.3c+ OR BSD-2-Clause
 \NeedsTeXFormat{LaTeX2e}[1994/06/01]
 \ProvidesPackage{beamerfontthemetuos}
      [2016/08/20 v1.1  LaTeX presenation class following the cooperate design of The University of Sheffield]
diff --git a/tuos-presentation/beamerinnerthemetuos.sty b/tuos-presentation/beamerinnerthemetuos.sty
index e41a167..036787b 100644
--- a/tuos-presentation/beamerinnerthemetuos.sty
+++ b/tuos-presentation/beamerinnerthemetuos.sty
@@ -4,10 +4,11 @@
 %%   This program can be redistributed and/or modified under the terms
 %%   of the LaTeX Project Public License Distributed from CTAN
 %%   archives in directory macros/latex/base/lppl.txt; either
-%%   version 1 of the License, or any later version.
+%%   version 1.3c of the License, or (at your opinion) any later version.
 %%   OR
 %%   The 2-clause BSD-style license.
 %%
+%%   SPDX-License-Identifier: LPPL-1.3c+ OR BSD-2-Clause
 \NeedsTeXFormat{LaTeX2e}[1994/06/01]
 \ProvidesPackage{beamerinnerthemetuos}
      [2016/08/20 v1.1  LaTeX presenation class following the cooperate design of The University of Sheffield]
diff --git a/tuos-presentation/beamerouterthemetuos.sty b/tuos-presentation/beamerouterthemetuos.sty
index 0be8f76..437bc58 100644
--- a/tuos-presentation/beamerouterthemetuos.sty
+++ b/tuos-presentation/beamerouterthemetuos.sty
@@ -4,10 +4,11 @@
 %%   This program can be redistributed and/or modified under the terms
 %%   of the LaTeX Project Public License Distributed from CTAN
 %%   archives in directory macros/latex/base/lppl.txt; either
-%%   version 1 of the License, or any later version.
+%%   version 1.3c of the License, or (at your opinion) any later version.
 %%   OR
 %%   The 2-clause BSD-style license.
 %%
+%%   SPDX-License-Identifier: LPPL-1.3c+ OR BSD-2-Clause
 \NeedsTeXFormat{LaTeX2e}[1994/06/01]
 \ProvidesPackage{beamerouterthemetuos}
      [2016/08/20 v1.1  LaTeX presenation class following the cooperate design of The University of Sheffield]
diff --git a/tuos-presentation/beamerthemetuos-presentation.sty b/tuos-presentation/beamerthemetuos-presentation.sty
index d4973ad..10b2d19 100644
--- a/tuos-presentation/beamerthemetuos-presentation.sty
+++ b/tuos-presentation/beamerthemetuos-presentation.sty
@@ -4,9 +4,11 @@
 %%   This program can be redistributed and/or modified under the terms
 %%   of the LaTeX Project Public License Distributed from CTAN
 %%   archives in directory macros/latex/base/lppl.txt; either
-%%   version 1 of the License, or any later version.
+%%   version 1.3c of the License, or (at your opinion) any later version.
 %%   OR
 %%   The 2-clause BSD-style license.
+%%
+%%   SPDX-License-Identifier: LPPL-1.3c+ OR BSD-2-Clause
 \NeedsTeXFormat{LaTeX2e}
 \ProvidesPackage{beamerthemetuos-presentation}
    [2016/08/20 v1.1  LaTeX presentation style following the cooperate design of The University of Sheffield]
diff --git a/tuos-presentation/tuos-presentation.cls b/tuos-presentation/tuos-presentation.cls
index 6c796dd..ce225f6 100644
--- a/tuos-presentation/tuos-presentation.cls
+++ b/tuos-presentation/tuos-presentation.cls
@@ -4,10 +4,11 @@
 %%   This program can be redistributed and/or modified under the terms
 %%   of the LaTeX Project Public License Distributed from CTAN
 %%   archives in directory macros/latex/base/lppl.txt; either
-%%   version 1 of the License, or any later version.
+%%   version 1.3c of the License, or (at your opinion) any later version.
 %%   OR
 %%   The 2-clause BSD-style license.
 %%
+%%   SPDX-License-Identifier: LPPL-1.3c+ OR BSD-2-Clause
 \NeedsTeXFormat{LaTeX2e}[1994/06/01]
 \ProvidesClass{tuos-presentation}%
   [2016/08/20 v1.1  LaTeX presenation class following the cooperate design of The University of Sheffield]