The news is a warning to those link spammers didn't mend their ways even after Google Penguin update. There have been instances of webmasters running link farms by manipulating Google terms. One such link farm in Japan faced the Google's wrath recently. Reports state that Google has penalized a Japan based link network as they were reportedly trying to manipulate Google search results rankings.
The blog post writes:
In addition, we tell even before, there seems to be the case that measures would be carried out, such as violation of the Webmaster Guidelines in place without the knowledge of the webmaster. Previously it introduced the example of SEO firms, but it seems there is also be generated by the outsourcing of such advertising not only SEO skilled in the art. In order to prevent this, the web master you we recommend that you check from time to time and see whether subcontractors are doing what measures.
From sometimes in past, google has been running after spammy link networks. After pushing hard and penalizing link networks in Germany, Italy and Spain, Google makes it to the Japan. If you're from Japan, please go through your webmaster account to find if Google Japan has sent you a notice. Meanwhile, go through your backlink profile to check if your links are in well shape.