Only two days ago, Whole Foods CEO John Mackey slammed activist investor Jana Partners as “greedy b-stards” for pushing for a sale of his company. Jana has gotten the last word.

New York-based Jana stands to make more than $301 million from the sale of Whole Foods Market Inc. to Jeff Bezos’s Amazon.com Inc., according to data compiled by Bloomberg. That’s more than $6 million for each of the 48 trading days since the activist revealed its stake and suggested that the organic-food grocer consider putting itself up for sale.

Jana’s 8.2 percent stake cost the hedge fund about $794.5 million, according to the activist’s latest 13D regulatory filing, meaning it may have realized a gain of about 38 percent. A representative of Jana declined to comment.

In an interview with Texas Monthly, Mackey, the embattled co-founder of Whole Foods, had lashed out at Jana, saying that “these guys just want to sell us, because they think they can make 40 or 50 percent in a short period of time.” Before Friday’s sale agreement, the company had announced plans to shake up its board in a bid to ward off a full proxy fight with the activist.

Whole Foods shares climbed as much as 28 percent Friday, edging above the $42-a-share that Seattle-based Amazon agreed to pay for the grocer. That valued Austin, Texas-based Whole Foods at about $13.7 billion including debt.

Jana had recruited five co-investors as expert advisers and potential dissident director nominees. The five -- Glenn Murphy, Thomas Dickson, Meredith Adler, Diane Dietz and Mark Bittman -- collectively acquired a further stake for about $47.3 million, the 13D filing showed.

Jana’s most recent activist encounters have happened largely behind the scenes. In March, the hedge fund announced an agreement with Blackhawk Network Holdings Inc. to add two independent directors -- before it had even disclosed its 4.7 percent stake in the prepaid-payment network. In February, Jana, led by Barry Rosenstein, struck similar settlements with drugmaker Bristol-Myers Squibb Co. and jeweler Tiffany & Co. without any public scuffles.