Bingo! Inasmuch as PFE will likely offer PFE shareholders the option to exchange their PFE shares for ZTS shares*, and the exchange ratio will be dictated in large part by the share prices at the time of the offer, a higher share price for PFE will cause more quasi-dilution for ZTS when the exchange is consummated.
*As BMY did with MNJ.
“The efficient-market hypothesis may be the foremost piece of B.S. ever promulgated in any area of human knowledge!”