Activist group Defective By Design is calling for an international day of action against digital rights management (DRM) technology on 3 October.

They want to highlight the threat DRM poses to open-source software development, consumer rights, and the way it could be used to control and track consumer viewing habits of future next-generation DVD formats.

Defective By Design came to prominence when it launched a wave of protests outside eight Apple stores in June. The group is connected to the Free Software Foundation.

It claims that DRM restricts what users can do with the media they own, which is why the group calls itself Defective By Design.

Free Software Foundation president Richard Stallman explains: "The motive for DRM schemes is to increase profits for those who impose them, but their profit is a side issue when millions of people's freedom is at stake; desire for profit, though not wrong in itself, cannot justify denying the public control over its technology. Defending freedom means thwarting DRM."

Music download services make use of DRM. The major labels argue that DRM prohibits piracy of their copyrighted material.