Our friends at StyleFeeder have offered up some great data about the geographic sources of social media spam on their tech blog. The background: Philip Jacob, the founder of StyleFeeder, is a long-time anti-spam advocate, while also being a careful guy who doesn’t want to ruin the Net in the process of fighting nuisance online. At StyleFeeder, they are seeing a growing number of posts about illegal movie downloads, pharaceuticals, adn the usual spammy subjects. Along with his colleagues, he’s developed a tool called Assassin to identify the source of the posts and get rid of them on the StyleFeeder site. In the process, they’ve noticed that the vast majority comes from India (with the US next, Pakistan as a distant third, and China weighing in over 5% in fourth place).
The rest of the post examines a familiar ONI-style question: wouldn’t it be much easier for a US-based site simply to filter out users from India, Pakistan, and China, for instance? After all, it’s a for-profit company, with no revenues being generated through these markets. Much to their credit, Phil and co. are taking a different path.
Phil’s post ends with a great research question: “How widespread is this kind of blocking by startups who are susceptible to the armies of computer-literate Indian social media spammers? I’m wondering what other small companies do when faced with annoying users in countries that aren’t part explicitly part of their target markets. If our experience is representative, this challenge may be more widespread than most people realize.” In the ONI world, we study state-mandated Internet filtering. It’s a dream to be able to figure out how frequently corporate actors in one part of the world are filtering content in another on their own, for simple business reasons.
(My disclosures: I hold equity in Stylefeeder and am an unpaid member of its board of advisors.)
John Palfrey 
There are certainly cases in spam filtering where people have opted to filter out entire countries. In particular, I’ve seen posts from frustrated email admins that block out all Nigerian email to suppress 419 scams. While the effects may be gratifying in the short term the long term effects are likely damaging to the Internet. Particularly, as noted by Philip, if the technique becomes an accepted defense and fragments the Internet even more.
The end result would be web services that are designed to only work in approved countries. There are a few examples of this already on the web. Hulu doesn’t allow viewers outside the US and Youtube blocks certain videos from playback in specific countries. The Youtube case is a mixture of commercial and political justifications and documented at the ONI blog here: http://opennet.net/blog/2008/03/youtube-and-rise-geolocational-filtering