Last months I have lots of referrer spammers in my GA statistics. Their count is ~10x higher than count of legit visitors (my site is not very popular yet). I've turned on an option to hide known spammers in GA settings, but it didn't help at all. It seems these spammers are using scripts to spam directly to GA (i.e. they are not logged in my IIS).Is there anything I can do to stop these spammers?  UPD 10 months later, and they started spamming using fake target page names... and Google is still doing nothing about it.
How to fight off Google Analytics referrer spammers?
google analytics;spam;referrer;google analytics spam
The Spam is getting out of control. The list it's growing and it's time-consuming and not even efficient to add a filter for each of the spammers since most of them shows up for a few days and then disappear and a new one comes.There is a lot of misinformation, the most common mistake is recommending to use the .htaccess, this file blocks the access to the Website, although there are a few crawlers(5 or 6) than can be block, the vast majority of the spam never access your site is Ghost Spam.The best way to stop this type of spam (Ghosts) is by creating a valid hostname filter, the ghost spam use either a fake or not set hostname, so with this filter you don't have to add endless filters, one filter will take care of the old and new spam.. Been using this solution successfully for 3 months More information about this method here:https://stackoverflow.com/a/28354319/3197362