Boeing has been sued by shareholders who said the company prioritised profit over safety prior to the January 5 mid-air cabin panel blowout on an Alaskan Airlines 737 MAX 9.
According to a proposed class action filed on Tuesday, the aeroplane manufacturer spent more than four years after the October 2018 and March 2019 crashes of two other MAX planes - which killed 346 people - assuring investors it was "laser-focused" on safety and would not sacrifice safety for profit.
Shareholders said Boeing's statements were false and misleading because they concealed the "poor quality control" on its assembly line, and caused its stock price to be inflated.
Boeing's share price fell 18.9 per cent from January 5 to January 25, the day after the Federal Aviation Commission barred Boeing from expanding MAX production because of safety concerns.
The decline wiped out more than $28 billion of market value.
A Boeing spokesman declined to comment on Wednesday.
The lawsuit filed in the Alexandria, Virginia, federal court covers shareholders from October 23, 2019 to January 24 this year, and is led by Rhode Island General Treasurer James Diossa.
Other defendants include Boeing Chief Executive Dave Calhoun and his predecessor Dennis Muilenburg, and Chief Financial Officer Brian West and his predecessor Gregory Smith.
"This case has the potential to effect changes in Boeing's practices to protect passengers and ensure their safety in the future," Mr Diossa said in a statement.
The Alaskan Airlines flight had only just taken off from Portland, Oregon, to Ontario, California, on January 5 when a panel in the side of the plane's fuselage came detached mid-air.
The aeroplane, which was carrying 171 passengers and six crew members, needed to make an emergency landing.
No one died on the flight, but some passengers have sued Boeing and the carrier.
The blowout caused the US' Federal Aviation Administration to temporarily ground 171 MAX 9 planes, resulting in thousands of flight cancellations at Alaska Air Group and United Airlines.
On Wednesday, Boeing said it couldn't provide full-year financial targets because of uncertainty over its planes.
In a letter sent to investors and seen by the BBC, CEO Mr Calhoun reportedly said Boeing faces a "serious challenge", adding it was "not the time" to provide a financial forecast.
"We will simply focus on every next airplane," he reportedly wrote.
The firm also reported better-than-expected fourth-quarter results, which included a $30 million loss, $22 billion of revenue and $3.38 billion of cash flow.
