Billionaire investor Daniel Och is ceding a big chunk of his ownership in Och-Ziff Capital Management Group following a period of upheaval for the biggest publicly traded hedge fund firm in the US.

Och-Ziff said Thursday that Och-Ziff’s founder and several former managing directors would sell 35% of their shares to Och-Ziff’s executive managing directors in the form of a new share class. Och also intends to withdraw a portion of his money from Och-Ziff funds.