British data and analytics company Preqin, founded over two decades ago, has been acquired by BlackRock, the world’s largest asset manager, for a staggering £2.55bn. The sale will see Preqin’s founder, Mark O’Hare, receive a significant sum of £2.04bn through his family holding company Valhalla Ventures. The remaining £510m will be shared among Preqin’s management and employees. Preqin…