Cory Doctorow: DRM is no friend of business
13 March 2011 Last updated at 16:21 GMT
Many people who create and sell content put their trust in 'digital rights management' (DRM) software to protect their work from copyright theft.
But copyright activist, blogger and sci-fi author Cory Doctorow thinks content creators should steer clear of DRM.
He explains his reasoning to BBC Technology of Business reporter Fiona Graham at the Economist Big Rethink summit.