If shareholders had only kept bankers on a tighter rein, the financial crisis might have been stopped in its tracks, so the argument goes. This morning, 68 asset managers, pension funds and others signed up to the UK's new shareholder rulebook, a basic blueprint for the way shareholders should hold companies' management to account. But it is worth looking at how far this code has penetrated beyond "the usual suspects" to understand how effective it might be.

The overwhelming majority of the 68 sign-ups announced today fall into two types - either big UK pension funds or big long-only asset management companies, either based in the UK or US. They are the kind of institutions who have in the past signed up for pretty much every governance and responsible-investment initiative going.