Fwd: Re: Closed-source interoperability with the GPL

[Eion Robb]

Hi everyone,

I got in touch with the FSF about whether it was legal or not to have a
Skype-API plugin for libpurple.  He's come back with what I had thought;
that it's legal to do so.

I've attached his email below.

Does this end the disputes now? :)

Cheers,
--Eion

---------------------------- Original Message ----------------------------
Subject: Re: [gnu.org #345894] Closed-source interoperability with the GPL
From:    "Brett Smith via RT" <licensing at fsf.org>
Date:    Wed, October 31, 2007 9:04 am
To:      eion at bigfoot.com
--------------------------------------------------------------------------

Eion,

Thanks for sending those details about the Skype API.  After reviewing
them, I think you've already got the right idea: since Skype uses standard
message-passing mechanisms on Windows and GNU/Linux systems, and its
interaction with client programs is relatively high-level (i.e., there
aren't entire data structures being passed between them), I see no reason
to believe that your client software is derived from Skype.  And if that's
the case, there's no legal obstacle to writing a Skype client with GPLed
software.  Your plugin should be GPLed, of course, since it's derived from
Pidgin, but the GPL does not prohibit this sort of arms'-length
communication with proprietary software.

I hope this provides the sort of guidance you were looking for.  If you
have other questions or concerns, please let me know.

Best regards,

-- 
Brett Smith
Licensing Compliance Engineer, Free Software Foundation

Please note that I am not an attorney.  This is not legal advice.