The Linux Foundation did a break-down of who was doing what with the Linux kernel back in April 2008. The results, Linux: How Fast it is Going, Who is Doing It, What They are Doing, and Who is Sponsoring It, makes it crystal clear that big business is behind Linux.
At one time, it's true, Linux was a labor of love, but that was a long, long time ago. While I don't an exact date for when Linux transformed from being written mainly by enthusiasts to when it was being written mostly by paid developers, I suspect it came twelve months after October 2001.
October 2001? That was when IBM announced that it was investing a billion dollars in Linux. Within a year, then Bill Zeitler, IBM's senior vice president and group executive for eServer, told me in 2002 that "We've recouped most of it in the first year in sales of software and systems."
Big business wasn't just paying for Linux. Linux was already paying its own way in big business.
By January 24, 2008, when the 2.6.24 Linux kernel was released, over a thousand developers from over 186 companies were contributing to the Linux kernel. That doesn't count any work done on any particular Linux distribution or other open-source program.
Breaking it down farther, in the 2.6.24 kernel, it appears 13.9% of Linux had been written by people without a corporate backer. In the case of 12.9% of the contributors, the Linux Foundation was unable to pin point exactly who the programmers were working for. The rest, 74.2% was written by paid developers.
The top ten looks like this: Red Hat, 11.2%; Novell, 8.9%; IBM, 8.3%; Intel, 4.1%; Linux Foundation, 2.6%; independent Linux consultants, 2.5%; SGI, 2.0% MIPS Technology, 1.6%; Oracle, 1.3% and MontaVista, 1.2%. Just underneath the top ten, you'll find Google at 1.1%.
Except for MontaVista, a major embedded Linux vendor, MIPS, a powerhouse semiconductor OEM (original equipment manufacturer) and the independents, these are all major, billion dollar plus United States companies. It doesn't really sound like Linux is made in ma's basement does it?