On 21 May 2014 15:08, Frederik Ramm <frede...@remote.org> wrote: > I like the message but I am not sure if it really works, license-wise. > > Suppose I have my own data set with restaurant POIs, A. > > Now I take an OSM database with restaurant POIs, B. > > Now I compute the difference, B-A - "all restaurants that are in OSM but > not in my own data set". > > This database, B-A, is clearly derived and needs to be shared. However > it does not contain anything that is not already in OSM so sharing it > would be of little use to anyone. > > Now I build a restaurant finder web site that polls both databases, the > "A" and the "B-A" database. > > And you say: Because of this I now need to share A. > > But I don't see how this can ever be possible. At what point has A, > which has not been modified the slightest in the whole process, been > "tainted" with ODbL? The only thing that has any descendance from OSM is > the B-A database.
One possible argument (and I'm not sure whether it's correct or not) would be that while initially A and B are independent elements of a collective database, in order to run the query that works out B-A, then A and B (or at least the information required to run the query) are no longer independent. Therefore you've implicitly created a derivative database of (at least parts of) A and B, in order to run the query. If that's the case then either the (parts of) A+B derivative database must be shared under ODbL, or the parts of A used in the query and the details of the query must be made available. Robert. -- Robert Whittaker _______________________________________________ legal-talk mailing list legal-talk@openstreetmap.org https://lists.openstreetmap.org/listinfo/legal-talk
