In relation to the stock market , what does the expression Ex rights mean ?

Subscription Right is a privilege granted to owners of certain stocks to purchase newly issued securities in proportion to their holdings usually at prices below the current market price. Rights have a market value of their own and are actively traded. They are different from warrants in that they must be exercised within a relatively short period of time. "Ex-rights" in connection with the rights offering with a stock purchase means shares of stock that are trading without the rights attached. The Ex-rights date is the date on which a share of common stock begins trading "ex-rights", without the right.