Is it permissible to offer large quantities of shares for sale with the aim of lowering their price, then re-purchasing them at a low price, and selling them at a high price to achieve significant profits?

It is permissible to invest in the stock market (bourse) under conditions and regulations, such as the company's core business being permissible and its funds not being deposited in interest-based banks. However, manipulating stock prices in the bourse is impermissible, and those who engage in such manipulation bear the sin thereof.