Lawyers filed a class-action lawsuit against Twitter over the recent mass layoffs ordered by billionaire automaker and new owner Elon Musk.

Following the company memo informing employees of the impending layoffs, five workers filed the lawsuit. The memo had informed employees they would be notified of whether or not they would continue to work for the social media giant through an email on Friday morning.

The New York Times reported that a copy of the memo it had seen was sent from a generic email address labeled simply “Twitter,” and it made no mention of the specific number of jobs that were being cut. It has been reported in the media Musk intended to cut 50% of Twitter’s workforce.

Three of the plaintiffs had not yet been told whether they would be fired or not as of the time of legal filing, although they had lost access to their work email accounts. One had already been informed on November 1st that they had been fired.

Their lawyers are claiming Twitter has failed to abide by a US federal law called the Work Adjustment and Retraining Notification (WARN) Act. That law requires that laid-off employees must be given at least 60 days advance written notice if a company with more than 100 full-time employees intends to lay off at least 50 employees or one third of the total workforce. Reportedly Twitter intends to lay off at least 3,750 workers.

The lawsuit states, “Plaintiffs file this action seeking to ensure that Twitter comply with the law and provide the requisite notice or severance payment in connection with the anticipated layoffs and that it not solicit releases of claims of any employees without informing them of the pendency of this action.”

It is unclear if other Twitter employees will join the suit, however as it appears Twitter conducted its layoffs in compliance with the law. The lawyer who filed the lawsuit, Shannon Liss-Riordan, said to Bloomberg following the firing announcements, “I am pleased that Elon Musk learned something from the lawsuit we brought against him at Tesla. We filed this case preemptively to make sure a repeat of that violation did not happen.”

Liss-Riordan said her clients still had concerns over how the social media company choose which workers would be fired, and she said the worker terminated on November 1st appeared to have been targeted for termination as a retaliatory act. She noted they would continue to pursue that in court through the suit.