Punjab National Bank ranks third or fourth in the list of top 10 national banks in India. If you see the one year low its is 128 and the one year high it is 231. Today there has been a block deal of 386,305 shares at Rs 136 t a value of 5.26 Cr ( must be a big investor or a fund house that would hold it with a long term outlook).
Now if any well traded stock fall drastically, then people are tempted to buy it, this is called a "Bottom fishing" but for some it practically becomes a task of "Catching a falling knife." So, buying depends on your risk appetite and the ability to hold the share of a longer duration without needing to book a loss and exit.
What is generally followed is
1.Wait for the dust to settle
2.Don't buy when it triggers a lower circuit lock (a 10% fall)
3. Closely track until it turns green and starts to move up
4.Keep a watch for good news, a Government or a FM assurance that it will step in to stem the loss, most of the money has been traced and would be recovered in due course
5.Start entering in a progressive fashion of 10 -15% of the total you want to hold. For instance, if you want to have 500 shares of PNB, from tomorrow you can start pickingup 50 and then track and then start picking.
6. Two of the recent shares that have fallen and on the raise are Sanwaria and Godawari Power, if you see the monthly chart, you'll get an idea of how this works.