This excellent news piece from Ben Cohen at Channel 4 looks at the increasingly aggressive patent war being fought by the manufacturers of the world’s leading mobile phone and tablet devices - the most profitable products in the digital economy. “Where once the giants (Google and Apple) competed on features, they now compete on patents.”

The news feature looks in particular at the intellectual property surrounding the slide-screen technology used by millions to unlock a device. Apple claims the IP to this but a video tracked back to twenty years ago suggests that developers were already thinking of something remarkably similar long before the iPhone came into existence. Can the makers of Android defend legal claims from Apple that their IP has been infringed? And who will end up paying for the enormous legal fees and possible extra licencing costs?

This is a great example to use when thinking about intellectual property, barriers to entry in markets and lock-in effects