Pfizer Inc. (NYSE:PFE) still has room to maneuver if it is really intent on using its bid for AstraZeneca plc (LSE:AZN; NYSE:AZN) to relocate in the more tax-friendly U.K.

The trick is to provide enough cash to win over AZ's shareholders, while also using enough stock to re-domicile in the U.K. Pfizer has missed the mark twice thus far, but still has room to sweeten the cash component.