A senior executive has sued Supernal, the advanced air mobility affiliate of Hyundai Motor Group, after raising concerns that the company’s promotion of its future business timeline could mislead investors. She also contacted Euisun Chung to report what she described as unethical conduct.
According to the LA County Superior Court, Diana Cooper, Chief Partnership and Policy Officer at Supernal, filed the lawsuit on October 17th, alleging workplace harassment and gender discrimination. Defendants include Supernal, Hyundai Motor America, and Hyundai Motor Company.
Supernal is the Hyundai group entity responsible for developing an urban electric vertical takeoff and landing (eVTOL) air taxi. Cooper joined the company in its early formation phase as its policy lead, overseeing aviation policy matters.
The dispute began when Cooper challenged Supernal’s technology development schedule. According to the complaint, she warned in 2023 that the company was publicly promoting a development timeline it knew was unrealistic, potentially causing investor misunderstanding. The filing states that after she raised the issue, she was systematically excluded and subjected to retaliatory actions.
According to the complaint, Cooper was removed from Hyundai executive meetings and prohibited from visiting the company’s headquarters in Korea. She also alleges she was excluded from quarterly meetings along with another female executive. The filing states that Hyundai’s insufficient response exacerbated the dispute.
The LA Times reported on November 5th that Hyundai Motor Group “failed to recognize internal issues for two years and became aware only this year,” adding that Cooper sent a letter in April directly to the Hyundai chair describing mismanagement and unethical conduct.
The lawsuit lists several incidents of alleged unethical behavior, including: executives stating they would hire a prostitute for a client for $5,000; coworkers making inappropriate comments about Cooper’s body; and a male employee showing a video of his sexual activity.
The complaint also alleges wage and promotion discrimination. Cooper states she was paid less than male colleagues and moved from the Washington, D.C. office to the Irvine headquarters based on a promised promotion that was not fulfilled. Legal observers note that if the allegations are verified, the possibility of fraud charges “cannot be ruled out.”
Attorney Wonki Lee said, “If they promoted the schedule knowing it was unrealistic, that is intentional fraud. Even if they did not know, it still constitutes negligent misrepresentation, and they would remain liable for damages.” He added that punitive damages could apply if intent is established.
Hyundai Motor Group conducted an internal investigation for about three and a half months after receiving Cooper’s letter and dismissed Supernal’s CEO and CTO. The plaintiff argues that no protective measures were provided during this period.
As of 6 p.m. on November 17th, Hyundai Motor America had not responded to an official request for comment.
BY KYEONGJUN KIM [kim.kyeongjun1@koreadaily.com]
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