Is zakat obligatory on business assets in the form of bookstore merchandise, despite accumulating debts and project expansion costs, and how is it to be paid, what is its amount, and when is it due?

The majority of scholars hold that debt nullifies the obligation of zakat (definition) on hidden assets. Accordingly, if the trade goods exceed the debt – provided they reach the nisab (definition) (minimum threshold) and a hawl (full lunar year) has passed over them – then zakat is obligatory on the excess. However, if the trade goods owned by the zakat payer do not reach the nisab after deducting the debt, then no zakat is due on them. Therefore, if the trade goods owned by the zakat payer are sufficient to pay off all his debts – including the father's debt – and a nisab-worthy amount remains, and a hawl has passed over it starting from the time it became a complete nisab, then zakat becomes obligatory on him; otherwise, it does not.