Clicking on a Fortune: Facebook to Acquire Photo-Sharing Start-Up Instagram for $1 Billion

Facebook has just announced that it will acquire Instagram, the popular mobile photo-sharing service, for $1 billion in cash and shares.

The social networking giant posted on the acquisition, its biggest yet, on its site, as well as on CEO and co-founder Mark Zuckerberg’s Timeline on Facebook.

Photos are critically important for Facebook, which has been slow to innovate in the fast-growing mobile arena in the important consumer space. By contrast, Instagram has taken the arena by storm, with its delightful and elegant app and the motto, “Fast beautiful photo sharing.”

Consumers have responded (including me — it is the only non-communications app I use many times a day). The San Francisco-based company — with only 13 employees — had 30 million Apple iPhone users before it came to Google’s Android last week, where it got more than a million new users in just 12 hours.

Still, despite all the usage, Instagram had not articulated a plan for, you know, making money. Now, that will presumably be Facebook’s problem to solve.

The Facebook acquisition has been kept very quiet, with its CEO Kevin Systrom working on it in conjunction with new fundraising efforts that would have valued the company at $500 million. Liz Gannes reported on this effort last week, which was poised to close, in fact, before the Facebook deal was struck over the weekend.

Until now, Instagram has received Series A funding of $7 million led by Benchmark Capital just over a year ago, when it only had 1.75 million registered users.

Seed investors include Andreessen Horowitz — which did not follow on later — and Baseline Ventures. Also in the Benchmark round: Twitter creator Jack Dorsey, former Facebooker Adam D’Angelo and Chris Sacca.

In a blog post titled “Instagram + Facebook,” Systrom promised no change, except for the $1 billion mountain of cash:

“It’s important to be clear that Instagram is not going away. We’ll be working with Facebook to evolve Instagram and build the network … The Instagram app will still be the same one you know and love.”

Zuckerberg also promised that Facebook would keep Instagram independent, and that such a large purchase would be rare for the company, which is set to go public soon.

“This is an important milestone for Facebook because it’s the first time we’ve ever acquired a product and company with so many users,” he wrote. “We don’t plan on doing many more of these, if any at all.”

Here is the full press release from Facebook: