We just updated our page content describing link building for your website. Given the changes in the Google algorithm our approach for link building now also includes an assessment and cleanup of unnatural links to your site. These include any links from spammy sites that were put up just for the benefit of SEO. The benefit of these types of links is gone and to avoid penalizing your position in search results it is recommended to do a clean up of bad links. See the details here: https://www.redcarpetweb.com/link-building.html