An activist investor dropped its effort to replace Supervalu Inc.’s board of directors, the company said Tuesday, three business days after the company announced its sale to another major food distributor.

Blackwells Capital LLC, a New York investment firm that built a sizable stake in Eden Prairie-based Supervalu over the past year, proposed an alternative slate of board candidates for shareholders to vote upon at the company’s Aug. 16 annual meeting.

Both Blackwells and Supervalu were campaigning for shareholder support when the company last Thursday announced its current board had agreed to sell the firm to United Natural Foods Inc., a Rhode Island-based wholesaler that specializes in organic and natural foods.

Tuesday’s announcement removed the lone uncertainty that hovered over last week’s sale announcement.

The $2.9 billion deal valued Supervalu shares at a 67 percent premium and well above the prices that Blackwells paid as it built up its stake.

The investment firm had no comment when the deal was announced last week and did not return a request for comment Tuesday. A website that Blackwells created to reach Supervalu shareholders had been taken down by Tuesday morning.

Supervalu said the two sides agreed to chiefly cover their own expenses in the dispute but that it would pay Blackwells up to $700,000 to cover “certain fees and expenses” that it did not specify further.

“We are pleased to have reached this agreement with Blackwells, as we may now dedicate our full attention to continuing to operate our business and to completing the transaction with UNFI, which delivers a substantial premium and immediate and certain value to our stockholders,” Donald Chappel, Supervalu’s board chairman, said in a statement.

Supervalu’s sale announcement and Tuesday’s settlement of the dispute with Blackwells came before investment advisory services weighed in on the proxy battle.

Blackwells for months leveled a barrage of criticism at Supervalu’s board, chiefly that they presided over the strategic failure that resulted in the evaporation of 90 percent of the company’s market value since its peak in 2007.

Blackwells proposed that Supervalu sell its retail chains, including Cub Foods, the grocery-market share leader in the Twin Cities. United Natural Foods said it will sell Cub and Supervalu’s other grocery chains soon after its purchase closes, which is expected later this year.