Facebook’s “news feed” patent — more formally US patent number 7,669,123 for “dynamically providing a news feed about a user of a social network” — is a classic example of why the very idea of software patents is controversial.

The patent, filed in 2006 and granted on February 23 this year, claims to cover the monitoring of activities in a social network, storing them in a database, generating a list of news items related to those activities, selecting and sorting them, and displaying them to selected users with embedded links and advertising. In other words, it covers the “News Feed” that has been at the centre of Facebook since 2006 — and perhaps the similar news feeds since adopted by other social network sites including MySpace, LinkedIn and Google’s new Buzz.

This patent doesn’t cover every kind of news feed. Twitter wouldn’t be affected, reports All Facebook, since Twitter’s feed contains only the updates explicitly posted by users, not news of implicit actions such as “Sue Smith commented on John Brown’s status”.

But is this really anything new — patent law’s “novelty” requirement?

“They [Facebook] might be covering a sort of software or a kind of technology, but in essence what they’re doing is covering an activity that has probably been done for years but maybe just not with computers and not in quite the same technological way,” Kimberlee Weatherall, who teaches intellectual property law at the University of Queensland, told Crikey.

“The idea of getting updates about things that your friends are doing and then wanting to interact with that probably isn’t a particularly new idea and it did perhaps precede social networks.”

Andres Guadamuz, law lecturer at the University of Edinburgh, is blunter, calling it “a patent for trivial database information handling”.

“Where is the novelty? Where is the inventive step? This is pretty obvious stuff! RSS feeds and news streams are relatively old, and the only big difference here is that it is applied to social networks,” he wrote at his blog TechnoLlama.

There’s an echo here of the infamous 1-Click patent granted to Amazon in 1999 for the method of allowing customers to purchase using a single click on a “buy now” button and previously-stored address and credit card details. While the broadest claims of the original patent were subsequently rejected in 2007, Amazon resubmitted more narrowly and the US Patent Office has not yet made a determination. Since 2000, Apple has been licensing 1-Click for its iTunes Store.

Facebook’s patent may be a defensive move, something to be held in reserve as a bargaining chip should they be sued for patent infringement by another social network patent-holder.

Such patent battles are commonplace between tech companies. Apple vs Nokia over smartphone technology is just one recent example. Apple is also suing HTC, which makes Google’s Android-based Nexus One smartphone.

On the other hand, Facebook could use the patent offensively by suing competitors for infringement or demanding licence fees. That could well end up stifling innovation, particularly given so much software innovation comes from cash-strapped start-ups.

“Smaller companies can become targets because they don’t have patents that they can bring back in response,” Weatherall said. “The reality is patent litigation is really very expensive. I mean it’s expensive for both sides, but it’s certainly expensive if you end up on the receiving end.”