What is the ruling on the initial profits from shares, and the profits resulting from selling shares, for a man who bought shares in a company with the intention of participating in its annual profit, then later sold them due to difficult circumstances and gained large sums of money from them?

If you contribute to a company with the intention of benefiting from the annual stock dividends (not for trading), then the dividends are subject to zakat (definition) if they reach the nisab (definition) (minimum threshold) and a hawl (one lunar year) passes over them. However, if the stocks are held as trade goods for buying and selling, then both the stocks themselves and their profits are subject to zakat. As for the money resulting from the sale of stocks, if their zakat is considered zakat al-mustaghallat (zakat on productive assets), then a new hawl begins for this money, and both the principal and the profit are subject to zakat if they reach the nisab and a hawl passes over them.