Is Zakat due on hospital shares whose price has not changed in three years, knowing that the intention of the contribution was trade and profit?

The shares you intended for the hospital's income are subject to zakat on exploited assets (Zakat al-Mustaghallat); thus, their profit is subject to zakat if it reaches the nisab and a year has passed over it. However, if you intended them for trading and profit, they are subject to zakat on trade goods (Zakat Urood al-Tijara); in this case, one-quarter of one-tenth of their value is to be paid at the end of each year. The zakat for the past three years must be paid immediately if you had invested with the intention of trading.