I love it when I spot big brands go into the Google support forums seeking SEO help, but it is incredibly rare to see big SEO brands do that. Moz did just that, their own support forums weren't up to it. So Cyrus Shepard from Moz posted in the Google Webmaster Help forums about their Google SEO issue.
The issue is where Google has decided to canonicalize many of the /ugc/ URLs with the main /blog/ Moz URLs, so in this case, most of the YouMoz user generated content is outranking and virtually replacing the official Moz URLs in the Google search results.
Here is one example of many where the Local SEO section, which did rank very well in Google for [local seo] for https://moz.com/blog/category/local-seo has been replaced with https://moz.com/ugc/category/local-seo which is the user generated content version of Moz. Here is a picture:
As Cyrus notes, Bing ranks the proper URL fine.
It can be a Google bug, and truth is, Google should probably address it. But it is fun to see a SEO brand as big as Moz not be able to control (and I use that word on purpose) how Google lists their desired URLs and landing pages for their desired queries in the Google search results.
Forum discussion at Google Webmaster Help.