Referer Spam Is Annoying - And, It's Persistent

Recently, we've seen a few blog owners who are curious about odd trends in their Stats displays.

My numbers seem to go up steadily for a while, then drop. Then, they go up again, for a while, then drop again.

Rises and falls in traffic are normal. You'll never have the same number of people, viewing your blog, constantly. During some days and some hours, our readers are going to be elsewhere, and not viewing our blogs.


Any blog that doesn't have a completely homogenous audience worldwide will have obvious ups and downs in its statistics. At any time of the day, people are more likely to be elsewhere, maybe sleeping or working, and not viewing your blog. Some fluctuation in the numbers is normal.

If you're seeing a repeated gradual up trend followed by a sudden down trend, though, you may be seeing the effect of another problem - Referer Spam. Google periodically finds a way to remove numbers from specific referer spam techniques from our Stats logs.

Unfortunately, the numbers cannot be removed immediately - because referer spam cannot be blocked. Referer spam can only be detected, over time, by looking for suspicious numbers reported by multiple blogs, simultaneously, as part of a long term trend.

Unfortunately, the spammers who produce referer spam, like every other type of spam, are resilient, and resourceful. As they see their traffic, from abused Stats logs, drop, they can tell that Google is blocking them. So, they periodically change their technique, to make their activity less obvious. As they change technique, Google can't block them, so their abuse gets into our Stats logs again - and their numbers go up, again.

As the spammers are more successful, we see our Stats displays show a gradual up trend, in pageview counts. As Google detects and blocks them, we see our Stats displays show a sudden down trend, as the numbers are removed for all time ranges. Again, a normal rise and fall - just in a different pattern.

As long as we keep clicking on the links, we'll keep encouraging the spammers to abuse us. And they will keep changing technique, to keep from being blocked. Don't encourage the spammers.

1. Don't click on the links, that you don't recognise.
2. Don't publish the contents of your traffic logs.
3. Be patient, and let Google block the spam.