In its continued fight to keep SERP spammers at bay across the globe, Google has apparently penalized a Japanese-based link network.
Announcing the news on its Japanese Webmaster Blog, Google indicated they targeted the network for using practices directly against its Webmaster Guidelines.
Google hasn't officially indicated it penalized a link network directly since Nov. 2014, capping off a two-year time period (starting in 2012) when the search engine's Penguin update was a topic of regular discussion.
Are more manual link-related penalties coming?
Penguin, and the roll out of Penguin-related updates following its initial release, focuses on the methods and practices used by those optimizing for placement on Google's search results page, specifically those buying and selling links as a means to influence the perceived authority of their website listings.
It is difficult to know whether this signals the start of a period when webmasters and SEOs could see more frequent link-related updates and link quality penalties or whether it is just a single, direct penalty against one rogue actor that has been enacted in this instance.
"SEO firms" are often to blame (clarification, SEO firms using techniques outside of Google's much discussed Webmaster Guidelines) but really, link networks are often just relatively small, private "cabals" or groups promoting their digital destinations and content.
While the appeal and draw to use link networks and engage in practices that are outside the guidelines can certainly seem appealing to those responsible for search engine optimization, it's best to do your website's SEO initiative (as well as the company/enterprise) and future self a favor by avoiding the practice of buying and selling links altogether.