A significant development has occurred regarding Tata Sons' status. The company's application to remain private was rejected by the Reserve Bank of India. This decision has led to speculation about the potential listing of Tata Sons' shares on stock exchanges.

As a result, shares of various Tata Group companies have seen a notable increase. Gains of up to 20% were recorded, with some companies experiencing more modest rises of around 2%.

Further information on this development and its implications can be found in the original report, which provides more details on the affected companies and their respective gains.