> Google states that if, for example, Google Maps used PostGIS as its data store, and PostGIS used the AGPL, Google would be required to release the Google Maps code. This is not true. They would be required to release their PostGIS patches in this situation. AGPL does not extend the GPL in that it makes the Internet count as a form of linking which creates a derivative work, as Google implies, but rather that it makes anyone who uses the the software via the Internet entitled to its source code.

I don't really follow this.

The fact that the linking exception and the LGPL exist at all is enough to infer that the FSF/license authors consider linking against or otherwise using a piece of software as a component of a larger system is enough to make that larger system a derivative work of the smaller component, thus "tainting" (I use this work non-disparagingly) it with the copyleft provisions of the license.

If Google Maps (that is the suite of software running on Google's servers) uses PostGIS as its data store then it seems that without a judicial ruling on whether there's a legal difference between interfacing with a software component by linking against it and interfacing with a software component by using some other software interface, it's not possible to be so certain that there isn't an issue here.