Note: This method will only help fight FUTURE referral spam.
Step 1: Create a string that includes all the names of your referral spammers, for example: Petitions.whitehouse.gov|motherboard.vice|semalt|anticrawler|sitevaluation|buttons-for-website|buttons-for-your-website|-musicas*-gratis|best-seo-offer|best-seo-solution|savetubevideo|ranksonic|offers.bycontext|7makemoneyonline|kambasoft|medispainstitut
Step 2: Go to the Admin tab, select Filters and enter a name for your filter – keeping in mind there will be several.
Step 3: Click the Custom button and select Exclude and Filter field Campaign source.
Step 4: Add your string. Note: Since there is a character limit (approx. 100) to the Filter Pattern field, you’ll need to create as many filters as you need to remove all referral spam.
Step 5: Verify your string to make sure you’ve entered valid referrers: