What is a Rights issue?
A rights issue is a corporate action where a company offers its existing shareholders, the chance to buy additional shares in proportion to their holdings, at a discounted price. If the shareholder is eligible for the rights issue, their demat account will be credited with right entitlements (RE’s). RE’s can be used to apply for the rights issue or can be transferred by selling them on the market. If they are not sold or used for applying for the rights issue, they will expire worthlessly. See What is a Right Entitlement?
See the list of all corporate actions (DOC).
Read more about the rights issue by visiting zerodha.com/varsity/chapter/five-corporate-actions-and-its-impact-on-stock-prices