• Former Twitter exec Nick Caldwell, who led the company's Red Bird core tech team of engineers, is suing Elon Musk and X over millions in unpaid severance, and alleging a breach of contract.
• Caldwell resigned on Oct. 28, 2022, just after Musk completed his acquisition of Twitter.
• The suit is similar to one filed by four former Twitter executives, including ex-CEO Parag Agrawal, who say they are owed $128 million in unpaid severance.

Former Twitter exec Nick Caldwell is suing Elon Musk and X, alleging a breach of contract and a failure to pay severance and benefits he was owed after resigning from the company in 2022.

In the suit, filed in a California federal court on Wednesday, attorneys for Caldwell claimed that, following the close of Musk's $44 billion acquisition of Twitter, the company "cheated Mr. Caldwell and other executives out of a combined $200,000,000 in severance benefits by falsely accusing them of misconduct and purporting to fire them for 'Cause.'"

Caldwell's suit is similar to one filed by former Twitter executives, including ex-CEO Parag Agrawal, who claim they are owed $128 million in unpaid severance.

Caldwell is now chief product officer for Peloton and sits on the board of several other tech ventures, according to his LinkedIn profile. He previously managed a team of hundreds of engineers at Twitter as general manager of the Red Bird, or core tech, organization.

According to the complaint, Caldwell worked to retain key talent at Twitter up to the completion of the buyout, and then sent a letter to the company on Oct. 28, 2022, indicating that he was resigning "for good reason." Two days earlier, Musk tweeted a video of his entrance into the company's headquarters, and wrote, "Entering Twitter HQ — let that sink in!" Musk later changed the company name to X.

Twitter accepted Caldwell's resignation, which triggered a "Twitter Change of Control and Involuntary Termination Protection Policy," for executives leaving the company in good standing, Caldwell's attorneys argued.

Twitter told Caldwell his last day of employment would be Nov. 27, a month after his resignation letter. The company cut off his access to internal systems immediately and didn't stay in communication with him, the complaint says. By Nov. 27, Twitter was claiming that Caldwell was terminated for cause.

"With no factual basis, Musk simply accused Mr. Caldwell of misconduct as a ploy to evade paying him millions of dollars in severance benefits that Musk/Twitter owed to Mr. Caldwell," his attorneys wrote.

The suit notes that Musk brought in a number of relatives, investors and current and former employees from his other companies, SpaceX and Tesla, including some who worked "to deny the severance claims filed by Mr. Caldwell and the other executives as part of the severance benefit plan administration process."

The suit names Brian Bjelde and Lindsay Chapman who work at SpaceX, and Dhruv Batura who previously worked in finance at Tesla, as defendants alongside Musk.

Caldwell's attorneys say in the filing their client is owed around $19.3 million in severance benefits plus interest, and around half a million dollars, which represents the value of restricted stock units that he should have been paid in November 2022, and interest of around $3 million, plus attorneys' fees.

Musk and X didn't immediately respond to requests for comment. Caldwell's attorneys declined to comment and referred CNBC to the filing.

A few days before his resignation from Twitter, Caldwell shared a post on social media saying, "My wife and soulmate Tia Caldwell passed away suddenly the 15th of October. She was only 39 years old yet lived a full beautiful and accomplished life overflowing with love." The suit doesn't mention the death of his wife.

Read the full complaint — Nicholas Caldwell v. Elon Musk, X Corp. et al (Case 3:24-cv-02022) — below.