No body in sound mind will be pay more just for acquisition or merger purpose. Every single business entity will go for profits in whatever term possible. Of course PNB have their own strategy which most of the time its a long term game. They will see the fruit of this merger in 24 to 48 months. It's long haul. The fair value is derived by many professional after looking into company detailed auditing reports and what's the upside for the company in future.