BEIJING -  Lock-up shares worth around 40.66 billion yuan (about 5.67 billion US dollars) will become eligible for trading on China’s bourses next week. From Nov 20 to 24, lock-up shares of 67 listed companies will start trading on the Shanghai and Shenzhen stock exchanges. The aggregate market value of these shares is calculated based on the closing prices on Nov 17, the previous trading day. Under China’s stock market rules, major shareholders must wait one to two years before they are permitted to sell their shares.