TOKYO — U.K.-based investment group Silchester Intl. Investors has dramatically increased its buys of Japanese content shares since last spring, including Kadokawa Group Holdings, Bandai Namco Holdings, Hakuhodo DY Holdings and Asatsu, according to recent filings made to Japanese financial authorities.

Kadokawa filed a report Monday to Tokyo regional financial authorities showing that Silchester had boosted its stake in the media conglom from 9.1% at the end of August to 10.2% by Friday, making it the largest single Kadokawa shareholder.

Silchester has also taken a 13.88% stake in game giant Bandai Namco, a 6.06% share in Hakuhodo and a 12.81% stake in Asatsu, both ad shops with large media interests.

Silchester is a privately held investment firm that focuses on value stock plays. Its growing interest in Japanese media companies — at a time when most foreign investors are selling off their Japanese holdings — is a vote of confidence for the future strength of the Japanese media biz and its globally marketed pop-culture product.