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I built a site for a company a couple of months ago to bring it up to date: Proper coding, SEO, the works. Their old site was poorly compiled HTML*
Apparently, they used a service through a company that I'm assuming added back-links all over the place and likely some black hat SEO practices.
The site has been #1 for their target search term but now it's at the bottom of page 1.
Any ideas why the sudden drop? I'm even doing SEM through google, and that's where it's dropped.