diff --git a/future.lisp b/future.lisp
index 9e650e895ae41338906a9bd55f8df7fd7a883bc7..07d329f20a9081aafe0d29aec4cecbfcbc6411a1 100644
--- a/future.lisp
+++ b/future.lisp
@@ -3,6 +3,8 @@
 
 ;; This file is part of Eager Future2.
 
+;; SPDX-License-Identifier: LGPL-3.0-or-later
+
 ;; Eager Future2 is free software: you can redistribute it and/or
 ;; modify it under the terms of the GNU Lesser General Public License
 ;; as published by the Free Software Foundation, either version 3 of
diff --git a/library.lisp b/library.lisp
index 43b990efcf5eb1c32ffc8d0b6eae691fe51270fa..857b451d7c44e8486d84c4ac9aa80720d3b3b773 100644
--- a/library.lisp
+++ b/library.lisp
@@ -2,6 +2,8 @@
 
 ;; This file is part of Eager Future2.
 
+;; SPDX-License-Identifier: LGPL-3.0-or-later
+
 ;; Eager Future2 is free software: you can redistribute it and/or
 ;; modify it under the terms of the GNU Lesser General Public License
 ;; as published by the Free Software Foundation, either version 3 of
diff --git a/make-future.lisp b/make-future.lisp
index d60db527afdf340e1d6c9717f764a8e1d4f68a2d..5364a7f32d3ace93604927d79d896deeb70539c9 100644
--- a/make-future.lisp
+++ b/make-future.lisp
@@ -2,6 +2,8 @@
 
 ;; This file is part of Eager Future2.
 
+;; SPDX-License-Identifier: LGPL-3.0-or-later
+
 ;; Eager Future2 is free software: you can redistribute it and/or
 ;; modify it under the terms of the GNU Lesser General Public License
 ;; as published by the Free Software Foundation, either version 3 of
diff --git a/scheduler.lisp b/scheduler.lisp
index 2f038464822e2b918d15ab7c20750b45e5696c40..fec54e9003d51f7a4c908b24897367f459a73ef2 100644
--- a/scheduler.lisp
+++ b/scheduler.lisp
@@ -2,6 +2,8 @@
 
 ;; This file is part of Eager Future2.
 
+;; SPDX-License-Identifier: LGPL-3.0-or-later
+
 ;; Eager Future2 is free software: you can redistribute it and/or
 ;; modify it under the terms of the GNU Lesser General Public License
 ;; as published by the Free Software Foundation, either version 3 of
diff --git a/test/benchmark.lisp b/test/benchmark.lisp
index 3b0ba09c016b5dd57b2bd36f7a482a49c0fb4b0a..0bd89db3cecc7cd80992e68865eab7f7aad52044 100644
--- a/test/benchmark.lisp
+++ b/test/benchmark.lisp
@@ -1,4 +1,22 @@
-;;; The contents of this file are released into the public domain.
+;; Copyright 1993 Marc Feeley <feeley@iro.umontreal.ca>
+;; Copyright 2011 Vladimir Sedach <vas@oneofus.la>
+
+;; SPDX-License-Identifier: ISC
+
+;; Permission to use, copy, modify, and/or distribute this software
+;; for any purpose with or without fee is hereby granted, provided
+;; that the above copyright notice and this permission notice appear
+;; in all copies.
+
+;; THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
+;; WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
+;; WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
+;; AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
+;; CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+;; OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+;; NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+;; CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+
 
 ;;; Benchmarks from Appendix A of Marc Feeley's PhD dissertation:
 ;;; Marc Feeley. An Efficient and General Implementation of Futures on
diff --git a/test/test.lisp b/test/test.lisp
index b85688f67b11162700236b1585a769cabd275f88..b26ef6a2555e9fca1063bda0362ab6e0d2c9120e 100644
--- a/test/test.lisp
+++ b/test/test.lisp
@@ -1,4 +1,21 @@
-;;; The contents of this file are released into the public domain.
+;; Copyright 2010, 2011 Vladimir Sedach <vas@oneofus.la>
+;; Copyright 2011 Samuel Edwin Ward <seward@cytochro.me>
+
+;; SPDX-License-Identifier: ISC
+
+;; Permission to use, copy, modify, and/or distribute this software
+;; for any purpose with or without fee is hereby granted, provided
+;; that the above copyright notice and this permission notice appear
+;; in all copies.
+
+;; THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
+;; WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED
+;; WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE
+;; AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR
+;; CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS
+;; OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
+;; NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
+;; CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 
 (in-package #:test.eager-future2)