EDEN PRAIRIE, Minn. — Supervalu Inc. last month filed plans to spin off its Save-A-Lot chain of discount supermarkets.

Save-A-Lot would become a publicly traded company, with Supervalu shareholders controlling at least 80% of the enterprise, according to Supervalu’s filing with the Securities and Exchange Commission.

Supervalu president and chief executive officer Sam Duncan floated the idea of a spin-off last summer, commenting that such a move would unlock value for shareholders and permit Supervalu to focus on its other grocery stores, operating under such banners as Farm Fresh and Cub Foods, and its wholesale business, one of the largest in the United States. Duncan also said a spun-off Save-A-Lot would be a more ­competitive operator.

“As two distinct publicly traded companies, each of Supervalu and Save-A-Lot will be better positioned to focus on its respective businesses, customers and strategic priorities and to capitalize on growth opportunities,” Duncan commented in a letter to shareholders. “We believe Supervalu will be able to focus on providing wholesale distribution services to independent retail customers and operating its five regionally based traditional-format grocery banners. Save-A-Lot will continue to be a leader in hard discount grocery retailing in the United States.”

In its filing with the SEC, Supervalu said Save-A-Lot shares would trade on the New York Stock Exchange. The document did not indicate how much the company expects to raise from the share offering, and no date was set.

Supervalu officials noted that while they are preparing for a spin-off, “there can be no assurances that a separation or spin-off of Save-A-Lot will occur, or that any changes in the company’s overall operations will ­happen.”

Should the spin-off occur, the new company would be headquartered at Save-A-Lot’s current base in Earth City, Mo. Eric Claus, who was hired late last year as Save-A-Lot’s CEO, would lead the independent company. Claus, 59, has spent the past two-plus years as chairman, president and CEO of Red Apple Stores Inc., a chain of value retail stores based in Mississauga, Ontario.

Claus gained experience in hard discount and grocery retail in the United States and Canada. He served as CEO of Co-Op Atlantic and as president and CEO of A&P, first in its Canadian division and then overseeing U.S. operations between 2005 and 2009. Claus has also served as an adviser to private equity firms in the retail and packaged goods sectors.