You know, what—I looked into this a bit more, and you actually might be right about what caused this. Let me get you some more help.

I sincerely doubt it's a strategic choice not to have one, though.

Well, less a reason than an explanation. To be honest, I have no idea why they didn't use meta description when first establishing the site. It stands to reason, though, that by this point they don't have much incentive to add it.

I'm actually seeing some in their source, notably meta charset and <title>. You're right that there's no meta description, for example, which is interesting, but they don't exactly need it. ;)</p></title>

That strikes me as a pretty massive change in rankings for a simple on-page change. Even a site-wide one, like that. Have you run any analysis on your competitors to see if anything they did might be to blame?

Hi tybi-seochat!

I'm afraid there's no native way in Open Site Explorer to pull all of your links to PDFs. One option, though, would be to download the CSV with all of your links, and then filter out the ones whose targets don't end in .pdf.

Keep in mind, though, that even that likely won't be every link. The Mozscape index is designed to give you a great sense of your overall link profile, but it isn't exhaustive.

I have to say, GTAMP, I agree with all the above advice. As Jared notes, this isn't something that's going to wreck your traffic on its own. However, David is spot-on that it's certainly worth fixing if the cost isn't too high.

It can, yes. Also, Google's having acknowledged the schema doesn't necessarily mean that it will show the rich snippet on the SERPs. It's still good to have it, though, and you very well may start seeing it appear.

Hey Matt! Did Oleg answer your question? Or could you use more help?

Seconding adding noindex to tag pages. Unless you want those to rank—and I'm not sure why you would—that's a great way to avoid any issues.

I'm fairly certain it's not the worst duplicate issue to have, though.

Not using 301s could be a big part of the problem. Do your old backlinks all point to existing pages on the new domain?

Hi Matt! Did Martijn's response help? We'd love an update.

Hi Jeffrey! Did zeus1956's response help? We'd love an update.

Hi Malika! How'd it go? Did everything work out?

Hi Marketing_Today! Ever work this out?