U-Boot is Free Software. It is copyrighted by Wolfgang Denk and many others who contributed code (see the actual source code and the git commit messages for details). You can redistribute U-Boot and/or modify it under the terms of version 2 of the GNU General Public License as published by the Free Software Foundation. Most of it can also be distributed, at your option, under any later version of the GNU General Public License -- see individual files for exceptions. NOTE! This license does *not* cover the so-called "standalone" applications that use U-Boot services by means of the jump table provided by U-Boot exactly for this purpose - this is merely considered normal use of U-Boot, and does *not* fall under the heading of "derived work" -- see file Licenses/Exceptions for details. Also note that the GPL and the other licenses are copyrighted by the Free Software Foundation and other organizations, but the instance of code that they refer to (the U-Boot source code) is copyrighted by me and others who actually wrote it. -- Wolfgang Denk Like many other projects, U-Boot has a tradition of including big blocks of License headers in all files. This not only blows up the source code with mostly redundant information, but also makes it very difficult to generate License Clearing Reports. An additional problem is that even the same licenses are referred to by a number of slightly varying text blocks (full, abbreviated, different indentation, line wrapping and/or white space, with obsolete address information, ...) which makes automatic processing a nightmare. To make this easier, such license headers in the source files will be replaced with a single line reference to Unique License Identifiers as defined by the Linux Foundation's SPDX project [1]. For example, in a source file the full "GPL v2.0 or later" header text will be replaced by a single line: SPDX-License-Identifier: GPL-2.0+ Ideally, the license terms of all files in the source tree should be defined by such License Identifiers; in no case a file can contain more than one such License Identifier list. If a "SPDX-License-Identifier:" line references more than one Unique License Identifier, then this means that the respective file can be used under the terms of either of these licenses, i. e. with SPDX-License-Identifier: GPL-2.0+ BSD-3-Clause you can choose between GPL-2.0+ and BSD-3-Clause licensing. We use the SPDX Unique License Identifiers here; these are available at [2]. [1] http://spdx.org/ [2] http://spdx.org/licenses/ Full name SPDX Identifier OSI Approved File name URI ======================================================================================================================================= GNU General Public License v2.0 only GPL-2.0 Y gpl-2.0.txt http://www.gnu.org/licenses/gpl-2.0.txt GNU General Public License v2.0 or later GPL-2.0+ Y gpl-2.0.txt http://www.gnu.org/licenses/gpl-2.0.txt GNU Library General Public License v2 or later LGPL-2.0+ Y lgpl-2.0.txt http://www.gnu.org/licenses/old-licenses/lgpl-2.0.txt GNU Lesser General Public License v2.1 or later LGPL-2.1+ Y lgpl-2.1.txt http://www.gnu.org/licenses/old-licenses/lgpl-2.1.txt eCos license version 2.0 eCos-2.0 eCos-2.0.txt http://www.gnu.org/licenses/ecos-license.html BSD 2-Clause License BSD-2-Clause Y bsd-2-clause.txt http://spdx.org/licenses/BSD-2-Clause BSD 3-clause "New" or "Revised" License BSD-3-Clause Y bsd-3-clause.txt http://spdx.org/licenses/BSD-3-Clause#licenseText IBM PIBS (PowerPC Initialization and IBM-pibs ibm-pibs.txt Boot Software) license ISC License ISC Y isc.txt https://spdx.org/licenses/ISC SIL OPEN FONT LICENSE (OFL-1.1) OFL-1.1 Y OFL.txt https://spdx.org/licenses/OFL-1.1.html X11 License X11 x11.txt https://spdx.org/licenses/X11.html