The suit was filed in Illinois, where Boeing is headquartered, by the parents of Rio Nanda Pratama, who died in the crash while en-route home to prepare for his wedding. It claims that the plane was unsafely designed.

Reports this week indicated that Boeing knew but did not inform pilots of a flaw in its new flight-control feature, affecting Boeing 737 MAX planes — of which Flight 610 was one. The planes have an automated stall-prevention feature that can, without warning, push the nose down so strongly that the crew cannot pull it up again.

“It is particularly surprising to hear from safety experts and the heads of pilots unions that Boeing failed to warn its customers and the pilots of its new 737 MAX aircraft about this significant change in the flight-control systems and failed to include appropriate instructions in its instruction manuals,” said Austin Bartlett, one of the lawyers representing Pratama’s parents.

Boeing’s share price has fallen by more than 8% in the last week, over concerns about liability. Attorney Justin Green told CNN that the plane-maker may indeed be held liable, noting: “Boeing had provided its customers prior to the service bulletin, but did not adequately inform pilots of the potential problem and how to respond to it.”

The stall-prevention system’s overreaction can be triggered by faulty sensors that are supposed to tell the plane’s systems at what angle the plane is flying. Investigators say this sensor failed on Flight 610, a 737 MAX 8.

The Wall Street Journal reported Thursday that Southwest Airlines replaced two malfunctioning sensors of this type on its 737 MAX 8s, as a precaution. This troubleshooting measure took place in the weeks before the Lion Air disaster.