Pfizer is a confusing company. While they are top notch, never has so much been spent for so little.
Pfizer today is around a $205 Billion Company today but to get there this is what they've done maybe over the last 20 years:
Bought Warner Lambert for $111 Billion Bought Wyeth for $68 Billion Bought King Labs for $3.6 Billion Bought Pharmacia for aroud $60 Billion Bought Anacor for $5 Billion Bought drugs from Baxter for $650 Million Bought Hospira for $17 Billon Merged Upjohn into Mylan Bought Arry Pharma for $11 Billion Bought Medivation for $14 Billion Failed trying to buy Allergan Failed trying to buy AstraZenica
So around 20 years ago Pfizer was worth around $200 billion and it spent close to $300 Billion Dollars and is now worth $205 Billion.
Pfizer acts as an Hedge Fund, and a very poor one at that.