ACME Labs Freeware License

All the free software available on the ACME Labs web site has a copyright notice like this one:

Copyright © 2000 by Jef Poskanzer <jef@acme.com>.  All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
1. Redistributions of source code must retain the above copyright
   notice, this list of conditions and the following disclaimer.
2. 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.

THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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.

So what does this legalese mean? This is a modified version of the BSD license. You may be more familiar with the Gnu Public License, since it gets a lot of press. Well, forget about that. The BSD license is very different. While the Gnu license puts all sorts of restrictions on what you can do with the software, BSD-style licenses say "Hey, do what you like, we don't care. Just let people know we wrote it, and don't sue us." That's really all there is to it. The first paragraph with the numbered items says you can do what you like with the code, as long as you keep our name on it. The original BSD license has a couple more provisions there, we got rid of those. The second paragraph, all in capital letters, is a standard legal boilerplate notification that tries to make it difficult for anyone to successfully sue us over the software.

By the way, FreshMeat has a nice list of different types of freeware licenses. There are quite a few besides BSD and GPL. There's also the OpenSource.org list of open source licenses, which is not quite the same as the freeware licenses.

Here are some questions people ask about the license:

"Can I use your software in a freeware product?"

Sure.

"Can I use your software in a commercial product? Do I have to pay you?"

Yes you can, and no you don't have to, although we certainly won't object to any checks you care to send our way.

"If I use your software as part of my product, do I have to include your source code? Or my source code?""

No. You're thinking of the Gnu license. Our license just says that if you distribute our source code then you must leave in the license text; but you are free to use it in binary-only form if you like, and put the license text in your documentation instead.

"Can I make my own version of your software?"

Of course.

"Can I distribute my own version of your software?"

Yes, although we'd prefer that you didn't. Having multiple versions of the same thing floating around is inherently distasteful. If you absolutely must distribute your own modified version of our software, please name it something else to avoid confusing people.

"Would you please send me a signed disclaimer, so my company's lawyers are happy?"

No. The license in the source code is sufficient.

"We don't want to put your license in our documentation or distribute your source, can we use your software anyway?"

We occasionally grant special permission for this sort of thing. A donation to ACME Labs will probably improve the chances.