At least a dozen business executives have endorsed Bill Ackman’s call to refuse to hire members of student groups at Harvard that signed on to a letter blaming Israel for Hamas’ deadly attack on Saturday that killed more than 1,200 people, including at least 22 Americans.

Jonathan Newman, CEO of salad chain Sweetgreen, was among a group of business honchos who seconded Ackman in urging that the signatories of the letter circulated by a coalition of 34 Harvard student groups that “hold the Israeli regime entirely responsible for all unfolding violence” be blocked.

“I would like to know so I know never to hire these people,” Newman wrote in response to Ackman’s post on X, formerly Twitter, on Tuesday.

“Same,” David Duel, CEO of health care services firm EasyHealth, wrote in response to Newman.

The backlash and possible blacklisting has led to a flurry of backpedaling by four of the initial student organizations attached to the inflammatory statement — while board members of other groups have quit in an effort to distance themselves.