diff --git a/COPYING.md b/COPYING.md
index 7f679a1..cbfa39d 100644
--- a/COPYING.md
+++ b/COPYING.md
@@ -1,54 +1,35 @@
 # License
 
-Libcubescript is licensed under the University of Illinois/NCSA Open Source License,
-a permissive, non-copyleft, BSD style license. The license text goes as follows:
+Libcubescript is provided to you under the terms of the zlib license, just
+like the source it was originally derived from.
+
+The software is originally based on the CubeScript implementation in the Cube 2
+game/engine, which by now serves mostly as an inspiration, as the code has been
+largely rewritten (though isolated bits of the original source may remain).
+
+For copyright holders beyond just CubeScript, please refer to Cube 2's original
+license file.
 
 Copyright (c):
 
 * 2001-2015 Wouter "aardappel" van Oortmerssen and Lee "eihrul" Salzman
-* 2016 Daniel "q66" Kolesa
+* 2016-2020 Daniel "q66" Kolesa
 
-All rights reserved.
+This software is provided 'as-is', without any express or implied
+warranty. In no event will the authors be held liable for any damages
+arising from the use of this software.
 
-Permission is hereby granted, free of charge, to any person obtaining a copy of
-this software and associated documentation files (the "Software"), to deal with
-the Software without restriction, including without limitation the rights to
-use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies
-of the Software, and to permit persons to whom the Software is furnished to do
-so, subject to the following conditions:
+Permission is granted to anyone to use this software for any purpose,
+including commercial applications, and to alter it and redistribute it
+freely, subject to the following restrictions:
 
-* Redistributions of source code must retain the above copyright notice,
-      this list of conditions and the following disclaimers.
-
-* Redistributions in binary form must reproduce the above copyright notice,
-      this list of conditions and the following disclaimers in the
-      documentation and/or other materials provided with the distribution.
-
-* Neither the names of libcubescript developers nor any contributors may be
-      used to endorse or promote products derived from this Software without
-      specific prior written permission.
-
-**THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
-FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
-CONTRIBUTORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS WITH THE
-SOFTWARE.**
-
-# Original copyright
-
-The software is originally based on the CubeScript implementation in the Cube 2
-game/engine, which by now serves mostly as an inspiration, as the code has been
-largely rewritten (though isolated bits of the original source may remain); it
-was provided under the zlib license and was:
-
-Copyright (c) 2001-2015 Wouter "aardappel" van Oortmerssen and Lee "eihrul" Salzman
-
-For copyright holders beyond just CubeScript, please refer to Cube 2's original
-license file. Permission was given by the original copyright holders to re-license
-the source code under the same license as the rest of OctaForge projects and this
-note now serves to credit the original authors.
+1. The origin of this software must not be misrepresented; you must not
+   claim that you wrote the original software. If you use this software
+   in a product, an acknowledgment in the product documentation would be
+   appreciated but is not required.
+2. Altered source versions must be plainly marked as such, and must not be
+   misrepresented as being the original software.
+3. This notice may not be removed or altered from any source distribution.
 
 # Bundled source