US-based asset management firm Blackstone Group is reportedly in talks to buy the London headquarters of American insurance giant Aon, which is part owned by Abu Dhabi. The building is owned by Rockpoint Group and the Abu Dhabi Investment Authority sovereign wealth fund and the deal is set to be worth in the region of GBP£330m (US$524m), the UK-based Sunday Times newspaper reported yesterday, without revealing its sources. Founded in 1976, the Abu Dhabi Investment Authority manages assets of around US$627bn and is ranked as the largest sovereign wealth fund in the world by the Sovereign Wealth Fund Institute.