Kernel developers' position on GPLv3

Posted Sep 26, 2006 1:44 UTC (Tue) by sanjoy (subscriber, #5026)
In reply to: Kernel developers' position on GPLv3 by sepreece
Parent article: Kernel developers' position on GPLv3

That is, you release work A, granting a covenant to allow downstream users to use any patented technology in that work. Downstream user creates a derivative work AB that adds to it an extension that infringes a patent that you hold, but that was not used in the work A. The current language seems to say that you are giving away the right to use ANY patents you hold that anyone uses in such a derived work.

As you quoted from the GPLv3:

If you convey a covered work, you similarly covenant to all recipients, including recipients of works based on the covered work, not to assert any of your essential patent claims in the covered work.

This language answers your objection, I believe. Here's how. Suppose that you distribute a modified version of GNU diff v8 and GNU diff v8 uses one of your patent claims. Then, yes, you've given up the right to assert that patent claim against a derivative work of GNU diff v8. And that's fair: You shouldn't be able to sue your recipients over what you distribute. You also give up the right to sue them for using your patent in GNU diff v8a, a derivative work of GNU diff v8.

But now one of the recipients makes GNU diff v9 by implementing a tricky compression method on which you hold patent claims. You can still sue him or her because you promised only "not to assert any of your essential patent claims in the covered work" (emphasis mine). You did not make the broader promise: "I will not assert any of my essential patent claims in the covered work or in any of its downstream versions."