Microsoft has vowed not to take patent infringement cases against open source software developers, but a body specialising in open source law has warned that the pledge is effectively worthless.
Microsoft has long been an opponent of open source software and advocate of privately, commercially-produced programs. The company stunned the software world this month when it announced a partnership with Novell to work on interoperability between its operating system Windows and Linux, the best known open source system.
As an offshoot of that deal, Microsoft pledged not to take suits against individual developers. "These are individuals who are creating code, contributing code, they're not being paid for that code. They're not creating it as part of their job," said Microsoft general counsel Brad Smith at the time.
Now the Software Freedom Law Centre has warned, in an open letter to developers, that the pledge is "worse than useless". Not only does the pledge only apply to single developers working in isolation – the opposite of traditional open source working methods – but it can be revoked at any time, the group warned.
"The patent covenant only applies to software that you develop at home and keep for yourself; the promises don't extend to others when you distribute," wrote SFLC chief technology officer Bradley Kuhn in the letter. "You cannot pass the rights to your downstream recipients, even to the maintainers of larger projects on which your contribution is built."
"Microsoft has explicitly reserved the right to change its terms at any time in the future. A developer relying on the pledge could wake up any day to find it revoked," said Kuhn. "A careful examination of Microsoft's Patent Pledge for Non-compensated Developers reveals that it has little value."
Kuhn went further than saying that it had little value, though. He said that the pledge was dangerous. "It's worse than useless, as this empty promise can create a false sense of security. Don't be confused by the illusion of a truce; developers are no safer from Microsoft patents now than they were before," he said.
The SFLC advises open source software developers and is funded through public donations and through the Open Source Development Labs, a non-profit open source advocacy group.