Demat account information

You have to go by the company regulations, that is what you have signed while accepting the employment offer by the company as a condition to be employed.   there is nothing wrong in it, it is common for all employees of the company, hence do not agitate the issue.  If you have been singled out on the issue and have been facing tough situations then you may seek legal recourse.  In my opinion maintain the cordiality instead of getting on heels over such sundry issues.

Just to clarify here. This was not a policy of the company when I joined, and this was introduced about an year post my joining the company.

I have no problem maintaining cordiality, but the company's official policy document on this matter lists not just equities, but almost all forms of investment (except Real Estate) and I fear they may reserve the right to ask for any employee's financial history (which in my opinion is not the company's business)

Once the Company formulates a policy meant for its employees, it need not give prior notice and obtain consent from the existing employees.  If any employee does not like to adhere to the policy, they are free quit.  As you are working in a prominent Investment Bank, they might have formulated the policy to know your investment portfolio to keep a watch on the employee's activities. 

At the same time the organisation may ask its employees to submit annual statement of assets and liabilities to verify whether the assets acquired are within the known means of the employee or not.  There is nothing wrong with your Bank for ascertaining such information and you should have any grievances for this policy.

Well said by expert Mr.Malipeddi Jagga Rao, you may follow his useful tips.