The acquisition of as many as 5.4 million shares would give Amazon another foothold in the grocery business.

GRAND RAPIDS, Mich. – SpartanNash Co. has agreed to sell a stake in the company to Amazon.com Inc.

The acquisition of as many as 5.4 million shares of outstanding stock would represent a 15% share of the grocery distributor and would give the digital retail behemoth another foothold in the burgeoning food retail business.

SpartanNash is a distributor of grocery products to independent and chain retailers, its corporate-owned retail stores and U.S. military commissaries and exchanges.

The company last week issued a stock warrant to an Amazon affiliate, NV Investment Holdings, enabling the Redmond, Wash.-based Amazon to become one of the grocery distributor’s largest institutional shareholders.

The move comes as Amazon is rolling out its new Fresh grocery store concept, which incorporates a mix of organic, premium and low-priced national brands; cashier-free checkouts; and online fulfillment through curbside pickup. Amazon in August opened its first store under the Fresh banner in Woodland Hills, Calif.  Another half-dozen openings are in the works, in California and Illinois.

With Americans still sheltering in place and cooking their own meals, the grocery business has been one of the few bright spots in the U.S. economy.

Amazon’s Whole Foods Market unit last month opened a warehouse-like facility in Brooklyn, N.Y., designed to fulfill online orders. The so-called “dark” store can relieve crowding pressure in nearby stores, where contract shoppers helping to fulfill online orders mingle with Amazon Prime customers heading to the stores to pick up the merchandise that they purchased online.

SpartanNash serves customer locations in all 50 states and the District of Columbia, Europe, Cuba, Puerto Rico, Honduras, Bahrain, Djibouti and Egypt. In addition to its grocery distribution business, it operates 155 supermarkets, primarily under the banners of Family Fare, Martin’s Super Markets, D&W Fresh Market, VG’s Grocery and Dan’s Supermarket.

Dollar General is SpartanNash’s largest customer, accounting for about one-sixth of its $8.5 billion in annual sales.