By Tomohiro OSAKI The Japanese owner of 7-Eleven said Friday it had rejected a takeover bid from Canadian retail giant Alimentation Couche-Tard, saying the proposal "grossly undervalues" the company. The proposed purchase of Seven & i Holdings would be the biggest ever foreign takeover of a Japanese firm, merging 7-Eleven, Circle K and other brands across Asia, America and Europe. As the world's biggest convenience store chain, 7-Eleven operates more than 85,000 outlets globally. While the brand began in the United States, it has been wholly owned by Seven & i since 2005. A letter from the Seven & i board to Alimentation Couche-Tard (ACT) said it was open to "engaging in sincere discussions should you put forth a proposal that fully recognises our standalone intrinsic value". "We do not believe, for several critical reasons, that the proposal you have put forward provides a basis for us to engage in substantive discussions regarding a potential transaction," it said.