No discussion of OSM would be complete without a discussion of licensing and copyright.  OSM makes this particularly complex because the project is in the process of changing their license from CC-SA-BY to ODbL.  For a full discussion, I recommend the OSM Wiki, but the short version is:

  • CC-SA-BY (Creative Commons, Share-Alike, with Attribution) is a license that says that anyone can use a work and modify it, as long as attribution to the original author is maintained and the terms don’t change for the derived work.  This isn’t particularly surprising, it’s a typical “open source” license, similar to the GPL.
  • ODbL (Open Database License) is a slight twist: with the ODbL, anyone can use the original data, but if you modify the data, you have to give back your changes.  You don’t have to make your derived works open source though.  (So under the ODbL if you build custom scenery out of OSM, your scenery doesn’t have to be open-source licensed, but if you ‘fix’ any roads, you need to submit the fixes back to OSM.)

OSM is CC-SA-BY now and is working to switch to ODbL.  Basically their lawyers realized that CC-SA-BY is great for images and text, but isn’t actually legal for databases (which is what OSM is).  The ODbL will protect OSM as it is – that is, as a “database”.  Since OSM is a huge open project, the license change is going to take a long time and lots of people will post lots of rants on lots of mailing lists in the process.

Here’s our plan: we are going to make the v10 global scenery abide by both the spirit and the legal requirements of both licenses.  (At least, I hope we are going to try to do this.  I am not a lawyer and wouldn’t mind if this was all a lot simpler.)

  • The version 10 DSFs will be CC-SA-BY.  This means that you can modify and redistribute the global scenery DSFs.  In the past, we haven’t officially supported this, but we’ve allowed it to go on in the community.  With version 10, modifying DSFs will be officially okay.  (Please note that copying the sim DVDs will not be okay.  You can modify our DSFs, but we are not inviting anyone to sell pirated DVDs!  X-Plane is still a commercial product!)
  • We are encouraging all users to improve OSM directly in the OSM database – we will not accept modified DSFs as a way to fix roads.  (This helps us comply with the ODbL.)
  • All of the scenery tools used to create the global scenery will be open source.

This last case is important because we do a lot of processing to the raw OSM data before we create the DSFs.  Technically we are required by the ODbL to “give back” thsoe changes, but the truth is that I don’t think anyone really wants the hundreds of GB of temporary files we create as we process.  So instead we will give back the tools that do that processing, so people can recreate our processed database as desired.  From my discussions with OSM community members, this is apparently an acceptable way to ‘give back’ our changes.

I should say that nothing is guaranteed here.  Heck, it’s even possible that OSM will change its license in a way that screws up the whole global scenery project before we ship.  (This is highly unlikely – I’m just saying that there is legal uncertainty with OSM that we haven’t had to deal with when using other data sources.)  But I think we’ll be okay; X-Plane’s use of OSM (to create a mash-up of OSM plus other data sources like SRTM elevation to create a derived copyrightable work like a DSF) is definitely one of the use cases that OSM wants to make possible.

About Ben Supnik

Ben is a software engineer who works on X-Plane; he spends most of his days drinking coffee and swearing at the computer -- sometimes at the same time.

8 comments on “OSM: Is This Legal?

  1. Hmmm – maybe we should switch the apt/nav data to the ODbL licence? It’s under the GPL right now, but the ODbL seems to make more sense for pure data.

    – Robin

    1. Hard to say…part of the airports are factual (this is the runway number, this is the airport name) but some of it is more like a composition (this is my WED line drawing of the taxiways). It sort of falls between. I’d recommend keeping with GPL because it protects the more important parts and everyone understands it.

    1. No idea – please see the other comments re: distribution. We have no idea yet what the future of non-release DSFs is, nor are we committing to anything now, having not had time to give it appropriate examination. It’s something we’ll certainly look into after v10 ships.

  2. This is not really the topic but since you talk about SRTM elevation data: are we going to have improved elevation data in europe and especially Switzerland (in google earth the mesh are extremely thin)?

    1. Yes, this is not really on topic. Sorry, I can’t play 20 questions regarding all aspects of the global scenery, particularly the ones that aren’t finalized yet.

  3. In the happy days a couple of years ago all we had was copyright laws and copyleft licenses like GPL V2 or CC-SA-BY that regulated how to deal with copyright in an open way. Then the whole intellectually property mess started and things like software patents in the USA and the European database directives started to pop up.

    So we now have GPL V3 that handles software patents and the new ODbL that deals with the European database laws.

    The European database directive is one of the weirdest laws imaginable, because it allows protections to databases even if all of their content is based on freely available data, but its still something you have to deal with.

    1. Right – and if there is an equivalent to the European DB law in the US, I am not aware of it, which means you get considerable “legal shear” across borders even among large Western capitalist economies.

      Plus, I don’t know how it is in Europe, but in the US, litigation isn’t a determination of correct adherence to the law, it’s a battle of attrition where money is the ammunition. A small company like LR doesn’t have the resources for a protracted battle – our staff is so small that hauling one of us in for depositions is nearly equivalent to seeking an injunction on all business activity. So the IP law provides a framework for companies to club each other, but it doesn’t necessarily provide a useful source of protection to everyone.

Comments are closed.