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I'm not aware of any off the shelf tools that will go back several years, so you'll probably have to use a more advanced, do-it-yourself solution. Almost any sort of scraper technology should work, from Screaming Frog, Scrapebox, SEOTools for Excel, etc. Here's an article explaining how to use SEOtools for Excel to do almost what you are asking.  http://wiep.net/talk/diy-link-building/branded-mentions-link-building/ The difference being that this article uses Mentions.net to find recent mentions, whereas you'll likely want to go to Google directly to collect your data - probably by using a custom scraper like Screaming Frog or Scrapebox. I don't have detailed instructions as I've never done it before (and it would take like 3000 words) but the basic idea is to scrape Google for your mentions using the tools described above, then use SEOtools for Excel to extract non-linking mentions. Hope this helps! Best of luck