While denying that it is against open source software, Microsoft has adopted a more subtle line of attack by criticising the general public licence which covers it.
Microsoft is painting the licensing scheme, which covers some open source software including the Linux kernel, as a potential minefield that could impose oppressive restrictions on those who develop applications using open source components.
Visiting Microsoft shared source product manager Jason Matusow stated several times during an interview with Computerworld that Microsoft is not anti-open source.
"People try to categorise Microsoft as being against open source. We're not. We like it and want to work with it," he said. "Fundamental source access is something people like and we have had to recognise that."
This is despite the fact that in February group VP Jim Allchin called open source an "intellectual property destroyer". Three months later, Microsoft executive Craig Mundie equated open source to the failed business models of dot-coms that gave away products and services hoping to gain a market toehold. In June chief executive Steve Ballmer referred to it as a "cancer".
Matusow acknowledges that Microsoft faces competitive pressure from Linux, and has responded with the shared source programme. The programme, which has been running in the US since January, allows Microsoft's biggest customers to view and debug Windows code. However, he says the company doesn't believe open source is commercially viable because of the GNU GPL (general public licence).
The licence, which can be found at www.fsf.org, says any software incorporating source code already licensed under the GPL will itself become subject to the licence. All modified versions of GPL software must be released back as free software. Another part of the licence says developers can charge for distribution of software developed under it.
Microsoft has published a document questioning the GPL at Microsoft, and Matusow warns that anyone considering using or developing open source software should take a hard look at the GPL and consult their lawyer. Otherwise they may have to turn any applications they develop using GPL code back as open source software, thus jeopardising their intellectual property. He also says because you can only charge distribution costs and not for the actual cost of the software the GPL is not a viable business model.
But David Lane, a Linux systems integrator and the organiser of an open letter to the government asking it to favour open source software, disagrees with Matusow's interpretation of the GPL.
"You're allowed to charge for the software but you have to keep the source code open."
Lane points out that the preamble to the GPL states, "When we speak of free software we are referring to freedom, not price. Our general public licences are designed to make sure that you have the freedom to distribute copies of free software -- and charge for this service if you wish "Lane says that's how he makes a living from his Christchurch-based business, Egressive. "The actual software itself, as Microsoft loves to tell you, is a fraction of the total cost of ownership. The vast majority of my income comes from integrating software and selling solutions. I sell hardware combined with software which is configured to meet the client's needs. In some cases I write software using open source. I can charge for that and I can even charge quite a lot, but it still comes in way lower than what integrators who use Windows charge because my clients don't have to pay for the Windows licences. Microsoft is trying to take advantage of the naivete of general business software users."
NZ Post chief technology officer Kerry Dukie says the state-owned enterprise runs Linux extensively internally and has used it to build commercial initiatives (which he declines to name citing commercial sensitivity).
He says he doesn't see the requirements of the GPL as an impediment to using Linux and GPL source in a larger initiative. "On the whole we're cognisant and aware of the restrictions imposed by the GPL. We know that if you use significant amounts of GPL code in certain ways you have to return the source code to the open source community, and that's not a bad thing. As long as you go in with your eyes open and choose which parts you need to protect. With an application you should develop the bits that really are your intellectual property from scratch but for the generic parts why not use all the stuff that's already been done?"
Richard Vowles of development tool maker Borland says the GPL isn't the only licence covering open source software.
"Very few products these days are licensed under the full GPL. Most companies now use the Apache software licence, which is totally open. In the open source world there are many different kinds of licence and you choose the most appropriate for your software."