Sorry I should've been clearer. I am aware of that, but since anyone can use the code, the most important thing for those using it is that what they have tired their product to is actively maintained. If they don't do the majority of the work to maintain it then I think of them as getting a free ride from whoever is actively maintaining it. I don't mean that as a negative, either. Every company gets free rides in some way or another. Web companies off those that pioneered the web, for example.
KDE originally built KHTML. WebKit however is mostly a product of Apple. They made it into the product it is today. Along with help from Google/RIM/etc. But it was mostly them since they needed it to work in Safari and iOS.