I have purchased shares through National Invest Trust (www.nit.com.pk). As you know that share prices increases and decreases. I have two questions to ask:

In the name of Allah, Most Gracious, Most Merciful

Assalaamu `alaykum waRahmatullahi Wabarakatoh

Shares are not a permissible form of investment. Kindly refer to the following link for a detailed article on the impermissibility of shares.
Shar'ii stance on Shares and Stocks

In regards to the bank investment, it will not be permissible to keep the profit as banks pay interest. You will only be entitled to keep your initial investment and all the earned interest will have to be distributed to the poor and needy without making the intention of being rewarded. The same will apply to the proceeds from the dividends of the shares.

And Allah knows best

Wassalam

Ml. Yusuf bin Yaqub,
Student Darul Iftaa

Concurred by:

Ml. Ehzaz Ajmeri,
Student Darul Iftaa

Darul Iftaa