The SEMalt spam has been around since at least June 2014, I got incensed enough to block them from my server and write up how to block them on Apache servers:

The SEMalt spam has been around since at least June 2014, I got incensed enough to block them from my server and write up how to block them on Apache servers: http://kohanikin.com/2014/filtering-semalt-referrer-spam.html http://kohanikin.com/2014/filtering-semalt-referrer-spam.htm... This post seems to describe a new technique where spammers never even visit your site in the first place, spamming the Google Analytics servers directly.