Final answer:
Pre-emptive rights are crucial for existing shareholders as they protect against ownership dilution when new shares are issued by giving current shareholders the option to buy additional shares first.
Step-by-step explanation:
The most important feature of the pre-emptive right is that the rights afford shareholders protection against dilution of their ownership when new shares are issued. This means that if a company decides to issue new shares, existing shareholders have the right to purchase additional shares before the company offers them to the public, allowing shareholders to maintain their proportional ownership of the company. This is important because it protects shareholders from having their existing shares diluted and potentially reducing their influence and value within the company.