The company's board of directors on Friday said the move was an effort to strengthen "safety management," and Muilenburg will continue as CEO, president and a director. The board elected current independent lead director David L. Calhoun to serve as non-executive chairman, the company said in a statement.
"The board said splitting the chairman and CEO roles will enable Muilenburg to focus full time on running the company as it works to return the 737 MAX safely to service, ensure full support to Boeing's customers around the world, and implement changes to sharpen Boeing's focus on product and services safety," the statement said.
Muilenburg said he was "fully supportive of the board's action."
"Over his 33-year career at Boeing, Mr. Muilenburg has developed extensive knowledge of, and unrivaled experience in, Boeing and the aerospace industry," Boeing stated in its proxy to shareholders at that time, issued only days after the 737 Max grounding. Only 35% of shareholders who voted on the proposal supported splitting the jobs.
The move by the board to split the roles was a surprise, partly because it was a half measure - not removing Muilenburg altogether, but clearly reducing his authority, said Richard Aboulafia, aerospace analyst with the Teal Group. But it could also be a signal that Muilenburg's CEO job is in danger, particularly if he can't get the 737 Max approved to fly again soon, he said.
"It's clearly meant as a measure to signal of change to the outside world, and partly as a way of saying there could be a bigger change to come," said Aboulafia.
Aboulafia said he would give Muilenburg a letter grade of C for how he's handled the crisis, and particularly bad marks for the way he's communicated to investors and the public. Shares of the company are down 11.3% since the most recent 737 Max crash, a loss of about $27 billion of market value.
"I suspect everyone, including the street, is giving him another couple of months," said Aboulafia.