Similarly irrelevant are the protective locks that recording companies put on files to try to stop pirates from copying and sharing them, so called digital rights management systems.

FORBES: Free? Steal It Anyway

Indeed, PublishOne's business plan is a good example of how digital-rights-management systems may work in practice.

ECONOMIST: Digital rights and wrongs

In a blog post Friday afternoon, the company announced the acquisition of Widevine , a Seattle-based provider of video delivery security and digital rights management tools used by studios, cable systems and channels to show content both online and on TVs.

FORBES: Google Buys Widevine

They include a dispute with Washington-based patent portfolio owner SoftVault Systems, which alleges RIM has infringed its anti-piracy DRM (digital rights management) technologies.

BBC: Nokia seeks Blackberry sales bans after patent dispute