Is Zakat obligatory on money obtained from selling a car that was purchased for the purpose of trade and profit, at its usual annual due date, or upon purchasing the car, or upon selling it?

This car is a trade asset due to the presence of two conditions that necessitate Zakat on it: ownership acquired through an exchange contract, and the intention of trade at the time of ownership. The annual cycle (hawl) of the wealth is not interrupted by its purchase; thus, Zakat is due on it when the hawl of the currency with which it was purchased is completed, because trade assets are subject to the Zakat of their origin. The profit follows the original capital in Zakat, as it is its growth.