LONDON/NEW YORK (Reuters) – Alan Schwartz knows how to play a long game. The executive chairman of boutique investment bank Guggenheim Partners spent almost 20 years cultivating Pfizer (PFE.N) boss Ian Read as a client. Schwartz, 65, had been working with Read since 2013 to find a European-registered company with which U.S. firm Pfizer could combine and shift its headquarters to a country with a lower tax rate, so-called inverting.