[knowtheory]

As a matter of course, MIT and BSD licenses are non-threatening to businesses and organizations who do not necessarily have software as their primary focus.

Non-software shops who may be interested in using a piece of software may balk at using GPL3'd software because they don't know what the legal ramifications are of failing to comply, or the knowledge/wherewithal/processes to do release the software that they're using.

Talking to people about BSD/MIT is really easy: "You can do whatever you want with it as long as you retain the license and copyright".

At the risk of getting into a FOSS license debate, i'd like to think that FOSS contributors do it out of a motivation other than license restriction (and hell a lot of people still rip libs off, even when they are GPL'd!).

[evgen]

I am sure that most FOSS contributors do it out of a motivation other than license restriction, but I am also certain that many potential FOSS contributors work for organizations that may have questions about contributing to a GPL project (not particularly valid concerns/questions, but the less you have to deal with the legal department the easier it is to get sign-off on contributing to a project...) When you are talking about semi-specialized software like numerical analysis tools it is quite possible that there is a latent pool of potential contributors in industry who would find it easier to contribute to a BSD/MIT project than a GPL one.

It is also the case that this is basically a library, and many who would have no problems using/contributing on a GPL application will balk when it comes to a library or framework.