Dan Och and a group of former executives of Sculptor Capital Management Inc. sued the hedge fund and proposed acquirer Rithm Capital Corp., saying the $676 million deal would shortchange investors in favor of protecting Sculptor Chief Executive Officer Jimmy Levin’s job.

Och, who left New York-based Sculptor in 2019, said Tuesday in a statement that he wants a Delaware judge to halt the buyout until a rival group led by Saba Capital Management’s Boaz Weinstein is able to present its higher bid to shareholders. Weinstein’s group, which includes billionaires Jeff Yass, Marc Lasry and Bill Ackman, has offered to pay $13 a share for Sculptor, which last week accepted Rithm’s $12 bid.

Sculptor directors backing Levin have made it clear that “they favor only one result — the preservation of management’s jobs and compensation, at the expense of shareholder value,” Och said. The suit was filed in Delaware Chancery Court.

A spokesman for Sculptor and Levin didn’t immediately return a call Tuesday seeking a comment on Och’s suit.

Shares of Sculptor rose 0.3% to $12.31, the highest closing price since May 2022. The stock has lost more than half of its value over the past two years.

Read More: Battle for Hedge Fund Sculptor Escalates as Rithm Boosts Bid

The lawsuit is the latest twist in Och and Levin’s yearslong battle over the future of Sculptor. Och tapped Levin to take over the firm, formerly known as Och-Ziff, in 2017, but the two later fought over compensation and control. Och — who remains one of Sculptor’s biggest shareholders — has since become a fierce critic of Levin’s handling of the fund.

“The proposed merger reflects just the latest step in a long line of actions by which the directors have demonstrated that they are beholden to Mr. Levin and place his interests over the stockholders’ interests,” Och’s lawyers said in the suit.

Last month, another Sculptor shareholder sued in Delaware over the Rithm deal, accusing Levin and the board of unfairly blocking investors from considering the Weinstein group’s higher bid. Judge Sam Glasscock III on Tuesday agreed to handle that case on a fast-track basis, according to Joseph Christensen, an attorney for the shareholder.

In his suit, Och asked the court to bar Rithm from voting new shares of Sculptor stock acquired from Delaware Life Insurance in the form of warrants. Those shares — added to those held by Sculptor’s current management — give Levin and his supporters two-thirds of the voting power they would need to approve the Rithm offer.

The case is Och v. Engel, 2023-1043, Delaware Chancery Court (Wilmington).

(Updates with details on second investor case in seventh paragraph.)