Is Zakat obligatory on the deferred dowry, the 'iddah (post-divorce waiting period) maintenance, compensation, and gold paid in installments from the husband's salary, after a full year has passed and it has reached the nisab (threshold)?

The deferred dower (mu'akhkhar al-sadaq) is a debt owed by the husband that must be paid zakat upon its receipt for past years, provided it reaches the nisab. The same applies to any amount decreed by the court as a settled debt. The zakat for this debt must be paid upon its receipt for the past years, or the zakat for each installment received must be paid upon its receipt, which is a quarter of a tenth (2.5%).