Elon Musk’s attorneys have sued the law firm which represented Twitter in the course of Musk’s takeover last year, accusing them of overbilling the social media giant. In the suit Musk’s attorneys accuse Wachtell, Lipton, Rosen & Katz, an elite law firm, of improperly obtaining a “gargantuan” payout for their representation of the micro-blogging platform. Musk’s X Corp, which owns Twitter, was the plaintiff in the lawsuit, which was filed in California Superior Court in San Francisco on Wednesday.

The previous management of Twitter had hired Wachtell when Musk indicated he might try to back out of his takeover bid to take Twitter private for $44 billion. Over four months of legal wrangling with Musk, the law firm represented Twitter, ultimately overseeing the closure of the deal when Musk finally relented and agreed to purchase the firm under the terms he had set out on October 27, 2022.

When it contracted the firm, Twitter had agreed to pay the firm based on an hourly basis. When the buyout was eventually completed, the firm was granted a “mammoth success fee” of $90 million. Calling the payout “unconscionable,” Musk said he considers it a violation of ethical duties by the firm as well as a violation of California law.

The complaint stated, “Fully aware that nobody with an economic interest in Twitter’s financial well-being was minding the store, Wachtell arranged to effectively line its pockets with funds from the company cash register while the keys were being handed over to the Musk Parties.”

The lawsuit notes it seeks to recover “any associated excess fee payment” and attorney feels which the law firm charged Twitter in the course of its representation. So far the law firm has not responded to any media requests for comment.

The lawsuit is just the latest that the social media company has become embroiled in, among them many accusing the company under Musk’s leadership of accumulating millions in unpaid expenses to vendors, landlords, and former employees. In addition, Musk has hinted Twitter may sue Mark Zuckerbeg’s Meta Platforms, over its new Twitter clone, Threads. Musk has indicated he believes his rival has used proprietary Twitter technology which it acquired by hiring former Twitter employees.