Provided they "take the best parts" by re-using their code. The license doesn't kick in if you reimplement their patented functionality in your own code.
You still don't legally get a patent license; if you don't have one and HP decides to drop a patent suit on you (say their printer business flops and they need cash), you're toast.
You don't get a patent license, I know. What I meant was that if a company is willing to license a patent by putting a so-patented bit of code under the Apache license, then they are likely to be willing to explicitly give a patent license to reimplementors as well.
However, can you incorporate a minimal portion of the HP code to get the patent license? Maybe just use one function or something, just to make it a derived work?
I think the licence text itself is fairly straightforward (as much as legal agreements can be "straightforward") about it:
each Contributor hereby grants to You a [forever lasting]
patent license to [do anything with] the Work
The key part being "the Work", which is the code (in source or binary form) that's covered by the Apache licence. A derivative work would be covered by this patent licence, but a clean-room re-implementation of a feature would not because you are no longer dealing with "the Work".
Are you sure about that? Not that it says much, but I would find that very counter-intuitive. I imagine the following discussion in the courtroom:
- You made a clean room implementation of our patent. You shall pay for that!
- No, I did not! I just copied/translated it!
- Well, then accept our apologies.
AFAIK, both translation and copying do make derivative works. For example, one cannot translate the latest bestseller and start selling it without agreement of the publisher of the original.
The boundaries of what defines a derivative work is a bit fuzzy, and how much you need to take from a work in order to create new work that would be classified as derivative is open to debate/common law.
Suppose that HP holds a patent related to the keyboard layout in webOS, of which the source code of their implementation is released under the Apache licence. If Apple took that code and mashed it into iOS, it would (I believe) clearly be a derivative work and protected by the licence. But suppose they didn't look at the code (or any material released by HP under the Apache licence), they just saw a picture/read a description of it/used it on a device and implemented it based on those experiences; in this case I think it's difficult to say that Apple's implementation is a derivative (and therefore protected) because of the lack of connection to the Apache-licensed work (except that their code produces the same runtime effect that HP's does, which I don't believe is necessarily covered by the Apache licence as they are separable from the original work).
