Should a revolutionary humanitarian food product be protected by commercial patent, when lifting restrictions might save millions of starving children?

That is the moral conundrum at the heart of a bitter transatlantic legal dispute.

On one side are the French inventors of Plumpy'nut, a peanut paste which in the last five years has transformed treatment of acute malnutrition in Africa.

At first I thought this would be just another "greedy company vs the world" story, but it's actually a little more complex.