GPLv3

Comment 1491: Clarifying example

The example given here is reworded slightly to make it clearer that it is acceptance of the patent license (a self-imposition of conditions) that activates the section, and that the effective terms of the patent license must actually prohibit exercise of GPL freedoms by downstream recipients. A distributor who accepts a patent license that does not activate this section may nonetheless be required to comply with the second paragraph of section 11.

Ok, I just made comment 1566 about this sentence before seeing this comment. The above explanation helps, but I'm afraid it was not at all clear to me from the actual license text. It was only after reading the text several times that I could see the possibility of this interpretation. Perhaps I am unduly influenced by its semblance to section 7 of GPLv2, which has been interpreted on the record by Eben Moglen to mean something different from the above. (He says that effectively any private patent license activates that section.)

If you really want to clarify this example, make it "if you accept a patent license that prohibits _you_ from passing along freedoms ...". But then it gets painfully tautological. So I still think it can be dropped without harm.