Over the past year much of the focus of open data activists like myself has been on getting data out of government and into the wider world, in part to allow us to monitor, understand and engage with the public bodies working in our name. Government data of the people, for the people, and by the people, if you like.

But there's a wider goal here, to allow the community to make connections between things, to bring together the disconnected data that we or our governments individually know, and so understand more about the world in which we live.

And the world in which we live today is one where the corporate world is more important and has more power than ever (including the power to bring the world's economies to their knees, as the financial crisis has shown).

To help make sense of this world - where companies are in all countries and at the same time none - we need a simple open way of keeping track of these companies, and tying it together with other data about them.

In a world of where Tesco, for example, isn't a single company, but over 190 of them in the UK alone, it's important that there's a way not just of easily finding all them (try the same search on Companies House), but having a permanent easy-to-use URL for each of them, which can be used by different people, different websites as a common identifier.

That's the goal behind OpenCorporates, a new website and service that's launched today to build an open database of the corporate world, and that's why we've imported all 3.8m UK companies (including dissolved ones), and have a web page (with a URL made up of their company number) for every one. And that's why we're importing the companies from other countries too – we started with Jersey and Bermuda, meaning there are now URLs for the companies google is using in its, er, corporate tax planning strategy.

But more than that, once you start to add information the separate parts of government hold on companies, you can do all sorts of things, such as show:

• the companies that supply the UK government and are now in administration

• or those that have environmental statements and have had Health & Safety Executive Notices issued against them?

• or how many Fishing & Fish Farming companies does the government buy services from? (answer: one, and it's the Duchy of Cornwall Oyster Farm Ltd)

It's a small start, yet already we've got nearly 4m companies, and millions of data on them, and gives the community a resource that is sorely needed. Crucially too, because this project arose from the open data community, we're using the share-alike attribution Open Database Licence, meaning you can reuse the information to your heart's content, even commercially.

Chris Taggart is co-founder of OpenCorporates, is a member of the UK government's Local Public Data Panel, and is founder of OpenlyLocal and OpenCharities

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