"I would say there is more work to be done," Ellen Broad, policy lead for the ODI, agrees.
So what data is available now?
There are 20,000 datasets on data.gov.uk, Cabinet Office minister Matthew Hancock MP said in a recent speech - an impressive sounding figure.
All Whitehall departments now regularly publish data online in some form or another.
However the information can be "incomplete and difficult to analyse," limited in accuracy as some datasets are not released or are heavily redacted; and constrained as transactions under £25,000 are rarely published, a 2014 Institute for Government report found.
When and how the data gets published - crucial for startups relying on dependable data- can also be sporadic. Just 19 percent of the data published by departments on data.gov.uk is classed as 'up to date'.
Vast swathes of data are unavailable as a result of complex, locked-down outsourcing contracts with private providers. Two-thirds of outsourced deals in Whitehall do not allow the government access to information on profit margins, according to the National Audit Office.
Open data principles are not "embedded in procurement rules," Dr. Rufus Pollock, cofounder of nonprofit organisation Open Knowledge, told MPs on the Public Administration Committee last year.
Local authorities are supposed to publish all spending over £500 online each month.
"All of them are now publishing the data in some form," Dr. Ben Worthy, politics lecturer at Birkbeck College, says.
However "not all do this regularly," according to procurement data startup Spend Network, which relies on government procurement data to operate.
Ironically spending data for the Cabinet Office, which leads on transparency and open data policies across government, is about a year out of date.
Officials have refused to release the data in response to a Freedom of Information request.
The Information Commissioner's Office has said it could serve an enforcement notice against the department but has previously often proved unwilling to take a tough stance, preferring instead to 'work with' wayward authorities.
Their case perhaps demonstrates the crux of the issue: how do you force unwilling organisations to publish their data?
Spend Network often has to submit Freedom of Information requests to get data out of foot-dragging councils and other bodies, something they say "takes a lot of time".
One issue is the lack of legislation to compel data release.
"Government has in general declined to legislate for open data, i.e. create new information rights," open data campaigner Owen Boswarva says.
However, for Shadbolt, the issue is not technical or legal, but cultural.
"Typically there will be a set of people who haven't got their heads round it, the issues around licensing and so on. We have 350-odd local authorities in this country, and they all have a different view on what they should and shouldn't be releasing," he says.
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