Can I re-license Academic Free License code under 2-Clause BSD / ITC?

Question

I want to fork a piece of code licensed under the Academic Free License. For the project, it would be preferable to re-license it under the ISC License or the 2-Clause BSD license, which are equivalent.

I understand that the AFL grants me things such as limitation of liability, but licensing consistency is much more important to the project, especially since we're talking about just 800 lines of code, a quarter of which I've modified in some way.

And it's very important for me to give these changes back to the community, given the fact that this is software relevant to security - I need the public scrutiny that I'll get by creating a public fork.

In short:

At the top of the file I want to say this, or something like it:

# Licensed under the Academic Free License, version 3
# Copyright (C) 2009 Original Author

# Licensed under the ISC License
# Copyright (C) 2012 Stefano Palazzo
# Copyright (C) 2012 Company

Am I allowed to do this?

My research so far indicates that it's not clear whether the AFL is GPL-Compatible, and I can't really understand any of the stuff concerning re-licensing to other permissive licenses. As a stop gap, I would also be okay with re-licensing under the GPL, however: I can find no consensus (though I can find disagreement) on whether this is allowed at all, and I don't want to risk it, of course.

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• Wikipedia: ISC License
• Wikipedia: Academic Free License

Answer 1

The AFL says:

1) Grant of Copyright License. Licensor grants You a worldwide, royalty-free, non-exclusive, sublicensable license, for the duration of the copyright, to do the following:

...

c) to distribute or communicate copies of the Original Work and Derivative Works to the public, under any license of your choice that does not contradict the terms and conditions, including Licensor's reserved rights and remedies, in this Academic Free License;

So as long as you choose a license that does exactly that, you're good. Seriously, though, changing a fork to a different license can often upset the original authors, who usually choose a license for a reason. One should generally honor their wishes.

Answer 2

Ask the original author for permission. Then anything is possible and allowed.