By Svea Herbst-Bayliss

BOSTON (Reuters). United Natural Foods Oak Street Real Estate Capital (NASDAQ:) Inc is working independently on biddings for U.S. food distributor SpartanNash Co. (NASDAQ:), sources familiar with the matter told Tuesday.

According to sources, United Natural Foods (a SpartanNash rival) is looking into a potential purchase of the entire business.

Oak Street, an investment company based in Chicago, reached out to SpartanNash last week to reiterate its interest to purchase real estate from the company valued at up to $1Billion. This was shortly after SpartanNash had been pushed by two activists to make changes.

Sources said there is not certainty about a deal. They asked to remain anonymous in private discussions.

SpartanNash Representatives and United Natural Foods representatives didn’t respond to comments, while Oak Street declined comment.

SpartanNash, which is based in Byron Center, Michigan and has a market value of $1.3 billion, owns 145 supermarkets, primarily under the banners of Family Fare, Martin’s Super Markets and D&W Fresh Market and operates commissaries for the U.S. military.

Last month, SpartanNash’s board was nominated by Macellum Advisors (formerly teamed up with Ancora Holdings Group and Macellum Advisors). These investors own approximately 4.5% stock of the company and are asking the board to reconsider a sale.

Representatives from the hedge funds refused to comment.

After appointing Tony Sarsam to its CEO, SpartanNash revamped its board in January. Although its stock price has gone up 33% in 2018, it’s down by 8% in the last five years.

In 2004, United Natural Foods bought SUPERVALU at a price of $2.9 billion. The acquisition was used to grow its grocery distribution network. United Natural Foods’ stock price rose nearly 30% over the past 52 weeks and is now valued at $2.7Billion.