Laid-off employees at the Space Exploration Technologies Corp. (SpaceX) in Hawthorne, Calif., are taking the Elon Musk-owned company to court over some 200-400 layoffs conducted on or about July 21.

The vehicle for the lawsuit is the Worker Adjustment and Retraining Notification (WARN) Act, which mandates that companies with 100 or more employees within a 75-mile radius must give 60-days advance notice when conducting mass layoffs. A mass layoff is defined as 50-499 employees within a 30-day period if they make up at least 33 percent of the employer's active workforce. Otherwise, the standard is 500 employees.

According to President Gwynne Shotwell, SpaceX had 3,800 employees in October 2013, but the website now lists only 3,000 employees.

The law firm of Feldman Browne & Olivares filed the suit for former SpaceX technicians Bobby Lee and Bron Gatling and is now seeking class action status to cover the other laid-off employees.

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