No surprise, but Red Hat remains the top corporate Linux kernel contributor, as reported by SDTimes. As I've reported before, Red Hat is the top Linux contributor by a wide margin, with IBM, the next biggest corporate contributor, coming in nearly seven percentage points behind Red Hat.
Greg Kroah-Hartman, a Novell employee and prominent Linux kernel developer, recently called out Red Hat's contributions (good) but has taken far too much time to criticize Canonical, creator of the popular Ubuntu Linux distribution, and its apparent dearth of contributions (not-so-good).
Mark Shuttleworth defends Canonical's contributions to Linux, and I tend to side with him on this. He writes:
We focus most of our effort on integration. Our competitors turn that into "Canonical doesn't contribute" but it's more accurate to say we measure our contribution in the effectiveness with which we get the latest stable work of upstream, with security maintenance, to the widest possible audience for testing and love. To my mind, that's a huge contribution.
Canonical contributes significantly to the ease of use of (desktop) Linux, and recently upgraded its efforts. These are important contributions.
Regardless, as I wrote back in 2006 when Oracle tried to undermine Red Hat by offering a competing Linux distribution without matching its ambition with Linux kernel contributions, those who contribute most profit most, at least when selling a Linux distribution. In open source, it matters a great deal that you not only offer source code, but also that you're the source of the code.
Those who contribute have the closest thing to "control" that true open-source communities provide. This is a key source of pricing power.