The founding family of 7-Eleven’s Japanese parent company has failed to secure the money to buy it out, the company said Thursday, months after they launched a bid worth over $50 billion to fend off a foreign takeover.

Seven & i Holdings, which sits atop a vast network of 85,000 convenience stores, primarily in Asia and the United States, said in a statement that it would assess alternatives, including the proposal from Canada’s Alimentation Couche-Tard that the founding family had rejected.

Junro Ito, an executive at Seven & i and the son of its founder, and Ito-Kogyo, the family’s asset management company, had begun their buyout attempt in November, after Couche-Tard launched its unsolicited takeover attempt.

Couche-Tard, which runs more than 16,000 Couche-Tard and Circle K stores in North America and Europe, made an initial offer worth $38 billion in August, which Seven & i rejected in September, saying it “grossly undervalued” the company. Couche-Tard returned the next month with an offer worth $47 billion.

If Couch-Tard succeeds, the deal would likely be the biggest foreign-led takeover of a Japanese company.

Seven & i’s stock fell 11 percent on Thursday.

The battle for control of 7-Eleven reflects the sweeping changes underway in corporate Japan, where the convenience store chain is considered a national treasure, making any foreign-led takeover a long shot.

Japan has long been regarded as impenetrable for foreign companies seeking mergers and acquisitions, and analysts have questioned whether Couche-Tard can run 7-Eleven better than Seven & i.

Officials in Japan have pushed Japanese companies for more than a decade to take steps — like giving proper consideration to takeover offers — to show they are open to moves that would financially benefit shareholders. The aim was to leave behind the age of fortresslike companies that could reject foreign takeover bids without deliberation.

Seven & i has said Couche-Tard’s proposed buyout would trigger competition investigations in the United States, where they are the two largest operators of convenience stores.

In its statement on Thursday, the Japanese company said it was working with Couche-Tard to determine if a proposal that addressed this regulatory issue was possible.