I think that the warning is regarding patents that are essential for standards, and VPx sholuldn't fall into that category, nor rounded corners, if ever that were patentable in the EU.
I see, then this warning isn't really useful since a lot of trolling and patent racket happens outside of standards. Inside standards it's actually much harder to do anything, like Google already learned with Motorola.
Prior art is a really hard defense to pull as far as I understand, however so far software patents in Europe are still pretty limited, I always understood one of the reasons Jolla is/was not going to the US was patents...
