Nikkei press reported 2015 ham, sausage market share in Japan. According to it, the top supplier was NH foods (Nipponham).
Figure: 2015 Ham, Sausage Market Share in Japan
|Manufacturer||Market share (%)|
|Prima Meat Packers||12.5|
Source is Nikkei Sangyo Shimbun newspaper, the article on 2016 July 25th.