According to Sankei reported [J], Circle-K-Sunkus, the 4th largest convenience chain-store, announced on November 17th that it would replace its own reward points system with e-commerce giant Rakuten’s Rakuten Super Points.
Sales ranking of convenience store chains (2011)
These 4 groups occupied nearly 90% of domestic market.
|Circle K Sunkus||980|
by each groups’ financial reports via Lawson’s 2012 annual report [J, pdf]