What is Unrestricted Open-Source Software?

"Unrestricted open-source software" is defined as publicly-available computer program source code, subject to Copyright, but provided free to everyone under a set of license terms which do not, in any significant way, inhibit or restrict the ability of recipients to use, reuse, modify, and redistribute the source code (or derivatives created by recipients) for any lawful purpose.

"Public domain software" is a closely related term, but public domain software is not subject to Copyright and may also refer to software not available in source code form.

"Free software" (defined here) is another related term with a confusing meaning: Contrary to what one might expect, "free software" is not in fact free of restrictions which prohibit many forms of reuse and redistribution. However, a more descriptive label, such as "only share alike software", wouldn't have had the same marketing impact as the term "free software" in helping to advance the societal goals of the Free Software Movement.

Why Is "Unrestricted Open-Source Software" Better Than "Free Software"?

1. Because it is unencumbered by social engineering goals.
2. Because it is unlimited in its permitted scope of application and reuse.
3. Because it can be mixed with other software without restricting combined works.
4. Because it can fully transcend the original intent of its creator/owner(s).
5. Because it is even more free than so-called "free software".

Why Is Unrestricted Open-Source Software Better Than Public Domain Software?

1. Because the original source of the code is known.
2. Because there remains an identifiable party (the Copyright holder) asserting ownership over the code and who may even be able to provide some assistance with it. (Note that by doing so, an open-source developer may well be able to earn a living without having to resort to development of proprietary software).

An Example Unrestricted Open-Source Software License

The simplified BSD license (from the Open Source Initiative):

Copyright (c) __YEAR__, __OWNER__
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:

    * Redistributions of source code must retain the above copyright
    notice, this list of conditions and the following disclaimer.

    * Redistributions in binary form must reproduce the above
    copyright notice, this list of conditions and the following
    disclaimer in the documentation and/or other materials provided
    with the distribution.

    * Neither the name of the __ORGANIZATION__ nor the names of its
    contributors may be used to endorse or promote products derived
    from this software without specific prior written permission.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

Simple, eh? Under 250 words! Compare that to the over 5,000 words comprising the latest version of the GPL, many of which strip away essential freedoms for software users and developers that would otherwise be preserved by the BSD license above.

For more reading, please visit the following sites:

• The Open Source Definition
• Wikipedia