Sculptor Capital Management Inc. founder Dan Och’s backing of a sweetened deal from Rithm Capital Corp. to buy the hedge fund firm is a “disloyal accord” funded by perks for the billionaire, according to a dissenting Sculptor investor.

Och agreed to drop his objections to Rithm’s $720 million buyout bid after securing “millions of dollars’ worth of unique consideration” not shared with other fund investors, Sculptor shareholder Gilles Beauchemin said Friday in an amended lawsuit.