[asterisk-users] Licensing question.

[Kevin P. Fleming]

On 11/09/2011 04:37 AM, A J Stiles wrote:
> On Tuesday 08 November 2011, Yaroslav Panych wrote:
>> Greetings
>>
>> I have found next paragraph in Licence file(source root)
>> "Digium, Inc. (formerly Linux Support Services) holds copyright
>> and/or sufficient licenses to all components of the Asterisk
>> package, and therefore can grant, at its sole discretion, the ability
>> for companies, individuals, or organizations to create proprietary or
>> Open Source (even if not GPL) modules which may be dynamically linked at
>> runtime with the portions of Asterisk which fall under our
>> copyright/license umbrella, or are distributed under more flexible
>> licenses than GPL."
>>
>> What does it mean? Does it mean I can write non-GPL modules(BSD, MIT,
>> etc)? Can I build my modules in common asterisk source tree(i.e. using
>> LOCAL_MOD_SUBDIRS="my_mod_subdirs_list" make ) or must use separate
>> tree? If so, then since Asterisk core does not accepts anything except
>> AST_MODULE_INFO(ASTERISK_GPL_KEY, ....) what I should do here?
>
> If you write modules that need to be compiled against the Asterisk Source
> Code, then the resulting compiled binaries are by definition derivative works
> of Asterisk.  The GPL already gives you permission to release those modules
> under the GPL.  And "Fair Dealing" / "Fair Use" provisions of copyright law
> mean you need no explicit permission to make use of those modules yourself for
> their rightful purpose.
>
> You require a special, separate licence from Asterisk to distribute compiled
> binaries which are derived works of Asterisk under anything but the GPL.
>
> Other people can, also under Fair Dealing provisions, compile their own
> legitimately-acquired copy of your module Source Code against their own
> legitimately-acquired copy of the Asterisk Source Code; but what they end up
> with may well be unredistributable.
>
> What you *can't* do is distribute your modules *as pre-compiled binaries*
> under any licence beside the GPL -- if they are distributed under any other
> licence, they *must* be compiled on-site by the end user.

This is not true. Distribution in source or binary form makes no 
difference; if you produce an Asterisk module (that falls under the 
'derivative work' classification), whether you distribute it in source 
or binary form you must distribute it under the terms of the GPLv2 
unless you have been granted explicit permission to do otherwise.

Of course, as I said in my original reply, anyone who has plans to 
distribute Asterisk-derived works and wishes to do us under any license 
other than the GPLv2 would be wise to consult legal counsel in their 
area to learn how the license affects their plans.

-- 
Kevin P. Fleming
Digium, Inc. | Director of Software Technologies
Jabber: kfleming at digium.com | SIP: kpfleming at digium.com | Skype: kpfleming
445 Jan Davis Drive NW - Huntsville, AL 35806 - USA
Check us out at www.digium.com & www.asterisk.org