Ranking the top Asset Management firms

You would have to break it down by asset class and even strategy within each asset class. There is no such thing as one firm that is #1 across the board. In fact, it is very uncommon for a firm that is strong in one asset class (i.e. public equities, fixed income, real estate, private equity, VC, etc.) to be strong in another. Even within a given asset class, there are often different strategies and areas of focus i.e. EM growth equities, U.S. small cap value, international value, on and on.