Legal Implications of using Openal in Opentk Commercially

Question

Myself and my friend are currently creating a game, which we plan on selling upon its completion. We are using opentk.

I read over this: http://www.opentk.com/node/532 , and it pretty well describes that this is perfectly legal. However, we are using the included openal standard included with opentk. The license that openal belongs to is somewhat ambiguous, I read in some places that it is under LGPL, and in other places that it is not. I've also heard about an "openal soft". I'm not entirely sure what the difference is, and which is included in opentk, and what I am allowed to do, and not to do with it.

Are we allowed to include the openal installer with our program so that the program will correctly launch for the user? Or will this incur possible legal implications?

Also, do we need to include legal information in/with the game regarding openal and its usage? Or are we fine simply using it?

Sorry for all the questions, and thank you anyone and everyone who responds to, and reads this, for your time.

Answer 1

OpenAL is an open standard (meaning anyone can read and use it) with several implementations, some of which are proprietary (generally patent protected). OpenAL Soft is one such implementation which is under the LGPL. Creative Technology maintains another confusingly called just OpenAL, which is now proprietary.

You must obtain a license from the developer for any proprietary version of OpenAL, but LGPL versions are free as in speech, but not necessarily open source, and that requirement doesn't extend to derivative works.

It is always a good idea to include any relevant license information pertaining to your software as distributed, but in this case you must include the LGPL license in the combined work (Section 4 - GPL). This is because the LGPL is based on the GPL (see LGPL Preamble):

This version of the GNU Lesser General Public License incorporates the terms and conditions of version 3 of the GNU General Public License, supplemented by the additional permissions listed below.

Which states in Section 11:

Each contributor grants you a non-exclusive, worldwide, royalty-free patent license under the contributor's essential patent claims, to make, use, sell, offer for sale, import and otherwise run, modify and propagate the contents of its contributor version.

And merely excepts Section 3 of the GPL, which is:

When you convey a covered work, you waive any legal power to forbid circumvention of technological measures to the extent such circumvention is effected by exercising rights under this License with respect to the covered work, and you disclaim any intention to limit operation or modification of the work as a means of enforcing, against the work's users, your or third parties' legal rights to forbid circumvention of technological measures.

Vis-à-vis Section 1 of the LGPL:

You may convey a covered work under sections 3 and 4 of this License without being bound by section 3 of the GNU GPL.