OSM data is licensed via the Open Database License (ODbL) - of particular interest to the folks in this consortium is the `share-alike` provision of that license, which posits that you can make derivative databases of the data (such as augmenting it with other data/metadata) as long as you assign the ODbL to the derivative data.
> "...if you improve our data and then distribute it, you need to share your improvements with the general public at no charge. A painless way to do that is to contribute your improvements directly back to OpenStreetMap."
It has a viral license, any data you mix with OSM data becomes open source.
Data sources that people commonly want to blend with mapping data have legal and regulatory restrictions with respect to privacy, data jurisdiction, acceptable use, statutory time limits, contract terms, etc. The OSM license terms are in conflict with legal and regulatory compliance requirements.
Not really. Any Derivative Data needs to be licensed under the same or compatible license IF it is Publicly Used [4.4a]. You can internally use it without issues. And you can have a Collective Database which includes it without licensing the entire database under the same license [4.5a].
You may disagree, but the legal departments of every organization I've worked for that has looked into the matter concurs with this opinion. It effectively prohibits many practical applications for which organizations want to use mapping data for more than rendering maps. Companies that do use OSM data have rigid policies that only allow it to be used in narrow contexts.
The loophole that most companies seem to have landed on is using OSM data to do parallel construction of private data, which technically avoids the Derivative Database problem.
This is particularly true for governments. I know the United States Geological Survey wanted to use OSM data for portions of their cartography, but can't because it's not public domain (as their products must be).
