Top Asset Management Firms. Following are the top 10 and top 50 largest asset and wealth managers in the world ranked by total AUM. BlackRock, Inc (NYSE: BLK) is the world's largest asset manager with total assets under management of over $4.7 trillion. BlackRock was established in 1988 and is headquartered in New York City, United States. The company has more than 70 offices in 30 countries and employs over 12,000 people. (1) - UBS's invested assets include Wealth Management (CHF925 b), Wealth Management Americas (CHF1,009 b) and Asset Management (CHF628 b).