Is Zakat obligatory on a sum of 2000, or on shares valued at 5040 dinars, or on a sum of 10000, while having outstanding debts?

Shares that cannot be disposed of are subject to the rulings of wealth over which one has no control; thus, zakat is paid on them once they are received, for one year. As for the money in your possession, zakat is obligatory on it if it reaches the nisab (minimum threshold) and a hawl (one lunar year) has passed over it. If you have debts, then if you own assets beyond your needs, such as a car or real estate, use them to offset the debt and pay zakat on all your wealth. Otherwise, subtract the amount of the debts from the money in your possession and pay zakat on the remainder, provided it does not fall below the nisab.