The report shows that Red Hat contributed 23,356 changes to the kernel since the release of version 2.6.12 on June 17, 2005, amounting to 12.4 percent of the total. The kernel is now at version 2.6.35.Version 2.6.12 is the point at which the use of the version control system git was initiated to manage development of the kernel.Among corporate contributors, Novell was next with 13,120 changes (7 percent), followed by IBM (13,026 - 6.9 percent) and Intel (11,028 - 5.8 percent)But the greatest number of changes was made by people who were classified as being of unknown affiliation (35,663 - 18.9 percent). Another category of developer, of "none" affiliation, also made a sizeable contribution - 12,060 changes or 6.4 percent.The report also listed corporate contributions since the 2.6.30 release. Here too, Red Hat was tops among the companies that sponsor development (6219 changes or 12 percent), followed by Intel (4037 - 7.8 percent), Novell (2625 - 5 percent) and IBM (2491 - 4.8 percent).The top category was the "none" group (9911 changes or 19.1 percent) while the unknown group figured sixth with 2456 changes or 4.7 percent.The report added one word of caution: "The numbers presented are necessarily approximate; developers occasionally change employers, and they may do personal work out of the office."However, it added: "But they will be close enough to support a number of conclusions."The report was first released under the aegis of the Foundation in 2008 and then updated last year; it is the brainchild of kernel developer and Linux Weekly News editor Jonathan Corbet who, before it was adopted by the Linux Foundation, used to present it at the annual Australian national Linux conference each year.Corbet is now being assisted by another kernel hacker, Novell employee Greg Kroah-Hartman, and Linux Foundation marketing executive Amanda McPherson.

The report illustrates the amazing growth and energy which characterises the kernel development project. According to the report, over the last 5-1/2 years, every day there have been 6683 lines of code added, 3774 lines removed, and 1797 lines changed.If one looks at those daily statistics since version 2.6.30, the lines of code added were 9058, lines removed were 4495 and lines changed were 1978. "That rate of change is larger than any other public software project of any size," the report noted.When the kernel was at version 2.6.12, there were 566 individual developers and 90 companies involved. Currently, those numbers are at 1187 developers and 184 companies."The companies at the top of the listing are almost the same, and Red Hat maintains its commanding lead here. But we see companies like Nokia, AMD, Texas Instruments, and Samsung working up to higher contribution levels as they increase their investment in Linux kernel development."This rise in development of Linux sponsored by embedded/mobile companies and their suppliers reflects the increasing importance of Linux in those markets, the report added.