Microsoft has made an historic move by submitting device drivers to the Linux kernel under a GPLv2 license.
Microsoft has had a chequered past with both Linux and its open source GPL licensing structure, so the move was a jaw dropper.
Here is a look at some of the milestones since Microsoft internal memos leaked in 1998 that attacked the open source Linux operating system as it began to pick up steam as an alternative to Windows.
Internal Microsoft "Halloween memos" attacking Linux leak out. These are two rather long documents purportedly prepared by Microsoft employees evaluating the risk factors of Linux to Microsoft's operating systems.
May - Craig Mundie, Microsoft senior vice president, says the GPL poses a threat to the intellectual property of any organization making use of it.
June - CEO Steve Ballmer one-ups Mundie, calling Linux a "cancer that attaches itself in an intellectual property sense to everything it touches. That's the way that the license works."
May - Then-Microsoft chairman Bill Gates equates the GPL to anti-capitalism at a Government Leaders' Conference in Seattle.
Microsoft begins its Get the Facts campaign extolling virtues of Windows over Linux. The campaign is disbanded in 2007.
November - Ballmer says Windows provides better intellectual property indemnification than its open source rivals.
2005 September - An oblivious recruiter sends vocal open source advocate Eric Raymond an e-mail pitch seeking his interest in a position at Microsoft
March - Microsoft opens Port 25, which is billed as an open source community at Microsoft
June - Microsoft begins hosting Codeplex, a Web storage site for developers.
November - Microsoft and Novell enter business and technology partnership to provide integration between Linux and Windows.
May - Microsoft claims Linux and open source violates 235 of its patents.
July - Microsoft makes $100,000 investment in Apache Foundation to become one of only three Platinum sponsors of the Apache Foundation (Yahoo and Google are the others).
July - Microsoft makes first code contribution to PHP, a patch to ADOdb, a data access layer for PHP.
July - Microsoft submits device driver source code for inclusion in the Linux kernel under a GPLv2 licence.
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