In The State of Dark Social in 2014, an update to his 2012 post, Dark Social: We Have the Whole History of the Web Wrong, Alexis Madrigal provides some clarity to dark social.

In short: Facebook.

“Dark social” describes Web traffic that appears to have no referrer – Web links shared via e-mail or instant message, in forums, or through other means. This traffic often shows up in metrics as “direct” – much like if it was bookmarked or entered into a Web browser manually – and can’t be tracked back to the source.

This dark traffic can comprise a substantial percentage of all incoming social traffic. Olsy Sorokin at Hootsuite notes that “dark social has been reported to be responsible for up to 60% of overall referral traffic for various Web sites.”

ChartBeat, which provided the original data Madrigal used, says dark social makes up about 30% of traffic to sites in its network, and much higher on mobile. These proportions vary site-to-site, but are substantial.

Recent ChartBeat research finds that Facebook mobile, Facebook desktop, and Reddit apps are potential dark social sources. They are at best inconsistent about attaching referral data to URLs. And these social networks have strong mobile presence – but they don’t often list as mobile referrers.

ChartBeat was able to identify the networks pushing traffic on mobile when looking closely at specific stories and correlating traffic.

Additionally, it discovered that the major social apps provide user agent strings when visiting linked URLs. It’s added that capability to its services and believes other service providers will begin to use this data as well.

Madrigal’s analysis of the ChartBeat findings, his own research correlating traffic against Facebook, and talking to other media sites indicates Facebook is a major source of the overall traffic originating in dark social.

Says Madrigal: “The takeaway is this: if you’re a media company, you are almost certainly underestimating your Facebook traffic. The only question is how much Facebook traffic you’re not counting.”

Hootsuite’s Sorokin offers some good suggestions to improve your strategy with regard to dark social:

  • Make sure your analytics are using user agent information.

  • Use shortened URLs in outbound links.

  • Stay up-to-date on Facebook algorithms.

And lastly, I agree with Sorokin that Madrigal’s original observation – “That the only way to truly optimise for ‘social’ is to make the content itself shareable, regardless of platform. Dark social is distributed, so there is no way to game the system.” – is still true.

Madrigal himself isn’t so sure: “… True person-to-person dark social appears to be less prevalent on mobile devices. Because what people like to do with their phones, en masse, is open up the Facebook app and thumb through their news feeds.”

I encourage you to read the original posts by Madrigal, ChartBeat, and Sorokin. They contain worthwhile detail and some provoking thought.