Facebook EdgeRank disaster - 90% drop in feed visibility

Heyo!
I’m managing a website that is primarily centered around user-generated content, historically 50% or more of our daily traffic has originated from facebook.

Late january, we experienced a sudden unexplained spike in facebook referral, followed by a near-complete flatline.
The amount of impressions per share has effectively been reduced to just under 10% of its original number, and the total amount of facebook traffic is currently at 5% of the average before this incident.
We’re thinking the spike may have triggered some kind of anti-spam detector and that EdgeRank, apparently without any human supervision or input, subsequently decided to kill our website.
We’re still clueless as to what caused the spike in the first place, but EdgeRank may very well have been the cause there as well: For a brief period in the initial phase of the spike, our impressions-per-share count was 20% higher than the previous average.

In any case, I’m hoping someone might be able to shed some light on this issue, or maybe even forward this post to someone at facebook who might be able to do something about it.

Needless to say, this is severely hurting our business and will likely lead to jobs being lost if it continues for much longer.

Here are a couple of handy graphs that illustrate the problem, courtesy of facebook’s “insights”-feature:

  • The number of shares and impressions across a 4-month span
  • Total clicks to our website during the same period

Through the various updates on the Facebook platform I’ve seen pages experience big shifts to EdgeRank, often correlated to a new direction in posting or sudden growth of fans [i.e. running a big contest]. Few have been as steep as what you’re seeing but if you grew fast enough I suppose it’s possible that the system caught up with you quickly, or to your point, some level of spam reporting / engagement was reached to trigger a massive shift.

If you’re willing to share, how do your clicks & like followings trend against the impressions? Any changes in how you post [via web vs api]?

These are the stats regarding share story conversion rate for the period. It’s been largely unchanged by the calamity, with some unusual fluctuations over the past week possibly brought on by the reduction of audience to a selection so small that it can no longer be guaranteed to represent any average.

Graph:

Another theory is related to the possibility that the edgerank algorithm is assuming that our content is appreciated by a niche, and should be hidden from the news feed of those that do not click on our content frequently enough. Our content is user-generated and spans just about every theme you can think of, and as such will on average not be consistently interesting for each facebook user. Despite this, each share has reliably generated about 3.75 clicks until recently.

As to the posting method, no changes have occured. Our main posting method has been via the old “Share this link”-functionality which presents a separate window together with the option of prepending the share with a text.
We have of course thoroughly inspected every commit that went live in the period prior to or around the spike, but the change seems to be unrelated to our own development timeline.