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I'm currently managing SEO for my company's website, and I'm getting into link building for the first time. As part of the process, I'm using Open Site Explorer to see who's linking into our competitor sites, to get a better sense of what's available to us in our particular avenue of e-commerce. However, I'm finding that our competitors are getting inbound links from high-authority sites pretty far afield from selling jewelry - census.gov, parallels.com, warnerbros.com, and others. I try clicking through to these links, but each link starts a download of a file. I've seen .f4v, .7z, and .apk files listed as inbound links to our competitor. How is this happening? Again, I'm new to link building, so there may be a simple answer here, and if so I apologize for asking. However, this seems really strange to me, and a difficult situation to confront.