Not sure if you follow buyout / buyout pricing much. Pricing run up due to buyout rumors is not included into setting the buyout price. They'll use a pre-buyout news stock price as a base for the premium (and at times as a weighted average of range of days). ie Dec 17th would be the base price for calculating the premium.
you can not ever read. I wrote why would anyone make public they was going to bid on a company in the mid 2014 without at least putting a non binding bid on the table and watch the share price climb for 6 months.
Kinda like now $25 -$29 that alone is almost a 7% increase in a week