Satisfying multiple licenses upon distribution

Matthew Flaschen matthew.flaschen at
Fri Apr 13 22:17:31 UTC 2007

Suraj N. Kurapati wrote:
> Matthew Flaschen wrote:
>> IANAL, but I don't think this license (Sleepycat + MIT) allows
>> incorporation of your code into software with simple permissive licenses
>> (e.g. BSD).  To do so, you would need to allow your code to be
>> distributed under the BSD license. The BSD license /does/ allow
>> modifications to be kept secret.
> Alright, but why is it not possible to satisfy both licenses?

First IANAL, but I'm fairly confident the below's correct: When code is
distributed under the BSD license, that always allows private
modifications.  If you say your code can be distributed under BSD (which
you're not doing here), then you're saying people can make proprietary
versions of it.

> Can't you just provide the source code taken/modified from my
> license along with the BSD/MIT distribution to satisfy both licenses?

If I put a work under BSD (regardless of what else it's under) I'm
giving people the right to make a proprietary version of the entire
work.  That's what the license says, and that's what it means.  Whether
I personally provide source is irrelevant if I tell others they don't
have to.  That means Sleepycat/MIT (which requires source code stay
available) can never be compatible with BSD.

> True, they are philosophically incompatible.

They are also legally incompatible.  I don't have the right to include
Sleepycat/MIT code in a BSD work.  If I did so, I would be telling
people they could make it proprietary.  I'm not the copyright holder, so
I can't give them that additional right.

> By incorporating code under my license, an MIT or BSD developer is
> not surrendering his entire project to my license

By doing that, he would be putting *your* Sleepycat/MIT code under BSD
(unless he chose to relicense the combination under Sleepycat).
Sleepycat/MIT doesn't allow that, so he would be breaking the law.

> That "extra work" is simply to make the source code
> (only for the portions under my license) available upon distribution.

Even if he did so, he would be giving others (through the BSD license)
permission not to provide source.

I'm not going to speculate any more about philosophical
incompatibilities.  The current SleepyCat/MIT license is not at all
compatible with BSD.  If you make a new license you think /is/, post it

Matthew Flaschen

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