What is the meaning of Subscription right?

Before a company offers a new issue of securities to the public, it may offer existing shareholders the opportunity to buy shares of the issue at a discounted price. That's known as a' Subscription right', or a rights offering. Usually you receive one right for every share you already own, although the number of rights you need to buy a share may vary. Rights are transferable, and may be bought and sold on the secondary market. They expire quickly-generally within a month-so you typically must act promptly to take advantage of them.