Internet giant Yahoo! has bought micro-blogging site Tumblr in a deal thought to be worth around $1.1bn (£723m).
Yahoo! chief Marissa Mayer confirmed the anticipated takeover in a statement posted on the site – in which she also said Tumblr founder David Karp would stay on as chief executive.
“I’m delighted to announce that we’ve reached an agreement to acquire Tumblr,” she said.
“We promise not to screw it up. Tumblr is incredibly special and has a great thing going.
"We will operate Tumblr independently. David Karp will remain CEO. The product roadmap, their team, their wit and irreverence will all remain the same as will their mission to empower creators to make their best work and get it in front of the audience they deserve. Yahoo! will help Tumblr get even better, faster.”
A statement issued by Mr Karp said: “Before touching on how awesome this is, let me try to allay any concerns: We’re not turning purple.
"Our headquarters isn’t moving. Our team isn’t changing. Our roadmap isn’t changing. And our mission – to empower creators to make their best work and get it in front of the audience they deserve – certainly isn’t changing.”
Experts say the deal is part of efforts from Yahoo! to revive the struggling company by attracting a younger, trendier audience.
Tumblr was founded in 2007 by American web developer Mr Karp as a ‘tumblelog’ – a mini blog where users post pictures, videos, links and songs – and within weeks the site had attracted 75,000 members.
Based in New York, the company now employs 175 staff and hosts 108 million blogs, upon which users have so far submitted at least 50.9 million posts.
In 2011 the company was reportedly valued at $800m (£526m).
According to the technology website AllThingsD, as part of the deal Mr Karp will receive a cash payment and stay at Yahoo! for four years, retaining control of Tumblr.
Yahoo! has been looking at a range of possible acquisitions since Ms Mayer took over last year.
She has vowed to revive the company, which has faded in the face of competition from Google.
The company’s acquisition of Tumblr would fit in with its strategy of attracting younger users.
A survey found Tumblr was more popular than Facebook among people aged 13 to 25.
But some Tumblr users responded in anger to news of the proposed merger.
“Dear Yahoo, Please don’t turn this safe haven into a data mine. Our thoughts are not for sale,” posted one, adding: “We came here because we didn’t want to be found. It was safe here. We could be ourselves.
"Purchasing this site will kill the core of what it is: the last remaining trace of humanity on the web.”
Another user wrote: “So yahoo is paying $1.1 billion for cat memes, porn and teenage girls with body image problems. They better not change Tumblr.”
One Tumblr fan has set up an online petition with the aim of preventing the deal going ahead, with the following message: “Stop Yahoo! from buying Tumblr!! If this happens, the entire interface will be changed, and millions of users will delete their accounts – me being one of them.
"Please, please, please sign this to stop this!!”
Internet entrepreneur John Battelle said in a blog post: “There are plenty of smart and appropriate takes on why this move makes sense.
"We’re all shifting our attention to mobile devices, and we’ve adopted the ‘stream’ as our preferred method of content discovery and consumption … and Tumblr was built from the ground up as an activity stream.”
Roger Kay at Endpoint Technologies said the deal “brings a social element that Yahoo! is missing and a set of new users”.
But he added: “Paying $1.1bn for a company with $13m (£8.5m) in revenue seems a little nuts to me. Those numbers aren’t even earnings, which are surely negative.
"So, even if Tumblr survives intact, Yahoo! is unlikely to get its $1.1bn back over any interval that falls within a human lifetime.”
Another issue for Yahoo! is that a lot of Tumblr’s content is pornographic which might dissuade some advertisers.
The site has also had problems with users posting copyrighted material.
Yahoo! recently failed in a bid to take over the online video site Dailymotion after the French government, which owns a stake, quashed the deal.