that he advised on their $60 billion takeover of Pharmacia in 2003. He also played a key role on the $16.6 billion sale of Pfizer's consumer healthcare unit to Johnson & Johnson in 2006 and helped the firm on the $2.4 billion sale of its Capsugel pill unit in 2011.
The close ties he had cultivated with Pfizer and Read paid off most spectacularly recently when Guggenheim was named lead adviser on the Allergan deal - which ranks as the second-biggest M&A transaction ever.
Schwartz was the last CEO of Bear Stearns before it was sold to JPMorgan Chase in 2008, and the following year he joined Guggenheim, which is based in New York and Chicago.
Wall Street veterans who know Schwartz describe him as a masterful adviser who uses his strategic insight and dealmaking skills, rather than wining and dining, to cultivate company executives.
"He has an ability to immerse himself in the details of a company's business, the competitive landscape and a potential transaction while simultaneously framing these issues in the big picture as a consigliere to CEOs," said Flexis Capital Managing Partner Louis Friedman, a former Bear Stearns investment banker who worked with Schwartz for years.
Schwartz and other bankers working for Pfizer in its negotiations with Allergan would refer to the merger project as "Pony" in written communications to keep its identity secret, according to one of the sources. His main counterpart on the Allergan side was Steve Frank, co-head of global healthcare investment banking at JPMorgan.
Pfizer's acquisition of Allergan will be financed mostly with Pfizer's stock, so Guggenheim was not handicapped by its limited ability to provide debt financing compared with bigger rivals.
In addition to Guggenheim as top adviser, Goldman Sachs Group, Centerview Partners Holdings LLC and Moelis & Co also advised on the deal.
Although Schwartz's previous attempt at inverting Pfizer had been unsuccessful, it led to him hiring an investment banker, a move that helped cement Guggenheim's relationship with the drugmaker.Schwartz advised Pfizer last year when it approached Britain's AstraZeneca Plc about a 70-billion-pound ($106 billion) bid, only for it to be snubbed. Also advising Pfizer however was Bank of America Corp's executive vice chairman of corporate and investment banking, Fares Noujaim, who Schwartz subsequently recruited to Guggenheim.
Noujaim, 52, is a Lebanese-American banker who had moved up through the ranks at Bear Stearns.
In 2008, before moving to Bank of America, he was vice chairman of Bear Stearns' board of directors while Schwartz was the bank's CEO.
Noujaim's departure last year cost Bank of America its close relationship with Pfizer as the bank was no longer included in its advisory line-up.