As the head of a publicly traded company -- THE most publicly traded company -- when asked on the D10 Conference stage about ongoing patent litigation, Apple's Tim Cook went straight into CEO mode.
Cook basically repeated his previous line -- that Apple shouldn't be the developer to the world. Apple wants competition but wants competitors to stop copying Apple and start making their own stuff. That's why Apple has been going after Android original device manufacturers (ODMs) like Samsung, HTC, and (now Google-owned) Motorola. (Apple has cross-licensing deals with Microsoft and has reached settlements with Nokia.)
As to whether or not the current patent system stifled innovation, Cook said Apple can't spend time and effort making a painting just for someone else to come along and sign their name on it. He said that was the worst feeling.
When asked about Apple copying other companies, Cook cast all counter-suits as morally questionable. In patents, there's a concept called FRAND (free, reasonable, and non-discriminatory), which basically means if you want your patent to become part of a standard, like 3G networking, you have to agree to license it to everyone else for roughly the same price, using roughly the same terms. Otherwise things like phones simply wouldn't work.
Cook says Apple has never sued over a FRAND patent, but claims their competition have sued, countersued, or been blocked from suing used FRAND patents (to try and force Apple to license proprietary patents they otherwise would not license.)
While that assertion seems to be true, Cook never got around to addressing the issue of Apple violating and getting sued for non-FRAND patents as well. (Which, for example, is why Apple users in Germany currently have no push email.)
We wouldn't expect Cook to address ongoing litigation in any way that may harm Apple, of course, so it's a question that would never be answered, but it does highlight the ongoing chaos that is the global patent system.
Which Cook himself did categorize rather adeptly -- as a "pain in the ass".