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Hi there, Yes that SEO Company told you right thing. Spammy backlinks are usually more annoying that hurtful. They may destroy your website reputation in Google. That’s why it’s important never to give them a chance to do that. There are some backlink types that you absolutely never want to connect with your website such as: Links from penalized domains Links from link bad directories Links from porn, pharma, online gambling etc Links from foreign language sites A large number of links from unrelated websites A large number of exact-match anchor text links Use tools like Ahrefs, Moz, SEMRush to find all these toxic link. At the end, you should check Google’s 'Disavow Links' tool to sort out your link spam problem. You can listen to Matt Cutts explain what it is and how it works here. Use the Disavow Links tool only after analysis of your backlinks profile. It can take a few weeks for Google to process the information that you upload. Your list will be incorporated into our index as we recrawl the web and reprocess the pages that we see. Please check following thread for more details: https://support.google.com/webmasters/thread/10239497?hl=en