
The company revealed earlier this week that it had struck a deal with UK-based company Datasift, allowing the firm to trawl through all tweets posted since January 2010 for anything said about clients’ products and services.
Datasift will use the information to help firms develop marketing campaigns and target influential users.
The company, which reportedly charges brands up to £10,000 a month to analyse tweets, is said to have a waiting list of up to 1,000 clients wanting to access the archive.
But online rights groups have slammed the move, with the Electronic Frontier Foundation describing it as “creepy”.
Meanwhile Big Brother Watch director Nick Pickles said: “People may consider tweets to be personal property but this deal makes clear they are not. Our personal posts on social media are yet another way for advertisements to be better targeted and that’s a very lucrative industry.
“It’s clear that if you’re not paying for a service, you are not the customer – you’re the product.”
And a Privacy International spokesman added: “People have used Twitter to communicate with friends and networks in the belief that their tweets will quickly disappear into the ether.
“The fact that two years’ worth of tweets can now be mined for information and the resulting ‘insights’ sold to businesses is a radical shift in the wrong direction.
“Twitter has turned a social network that was meant to promote global conversation into a vast market-research enterprise with unwilling, unpaid participants.”
But Datasift has hit back; a spokesman said: “It should come as no surprise to users that their tweets are archived – they can see every update they have ever sent on their timeline. Twitter was always created to be a public social network.”

