Originally designed to encourage invention, the patent system has been abused by large companies who build up patent portfolios so that they can use them as a tool to crush smaller competitors.
For a recent example of how IBM attempted to use the patent system to wipe out a technical innovator who dared to break IBMs monopoly on mainframe systems, see this article by Hesh Wiener.
After nearly two years of legal wrangling, IBM decided to buy out their upstart rival before the patents could be tested in court. See this follow-up article for details of the ignominious end to the story.
To discover how patents have become a disincentive to
software invention, read Richard Stallman's speech at
http://www.cl.cam.ac.uk/~mgk25/stallman-patents.html or watch the video on YouTube:
Last updated 12 Nov 2009