While Facebook urgently stiffens controls over how third parties access its users’ data – trying to mend its damaged reputation – attention is focusing on the wider issue of data harvesting and the threat it poses to our personal privacy.
Data harvesting is a multibillion dollar industry and the sobering truth is that you may never know just how much data companies hold about you, or how to delete it.
That’s the startling conclusion draw by some privacy campaigners and technology companies.
“Thousands of companies are in the business of harvesting your data and tracking your online behaviour, ” says Frederike Kaltheuner, data programme lead for foyer group Privacy International.
“It’s a global business. And not just online, but offline, too, via allegiance cards and wi-fi tracking of your mobile. It’s almost impossible to know what’s happening to your data.”
The really big data brokers – firms such as Acxiom, Experian, Quantium, Corelogic, eBureau, ID Analytics – can hold as many as 3,000 data points on every customer, says the US Federal Trade Commission.
Ms Kaltheuner says more than 600 apps have had access to her iPhone data over the last six years. So she’s taken on the onerous chore of finding out exactly what these apps know about her.
Not only is it difficult to know what data is out there, it is also difficult to know how accurate it is.
“They got my income totally wrong, they got my marital status wrong, ” says Pamela Dixon, executive director of the World Privacy Forum, another privacy rights lobby group.
She was examining her record with one of the merchants that scoop out and sell data on someones around the globe.
She found herself listed as a computer enthusiast – “which is a bit annoying, I’m not running around buying computers every day” – and as a runner, though she’s a cyclist.
Susan Bidel, senior analyst at Forrester Research in New York, who covers data brokers, says a common faith in the industry is that only “5 0% of this data is accurate”.
So why does any of this matter?
Because this “ridiculous marketing data”, as Ms Dixon calls it, is now determining life chances.
Consumer data – our likes, detests, buying behaviour, income level, leisure pursuits, personalities and so on – certainly helps brands target their advertising dollars more effectively.
But its main use “is to reduce risk of one kind or another , not to target ads, ” believes John Deighton, a professor at Harvard Business School who writes on the industry.
We’re all given credit ratings these days.
If the information flatters you, your credit cards and mortgages will be much cheaper, and you will pass employment background checks more easily, says Prof Deighton.