BEIJING -- Lock-up shares worth around 88.8 billion yuan (about 12.37 billion U.S. dollars) will become eligible for trade on China's bourses next week.

From Oct 23 to 27, about 5.2 billion shares of 65 listed companies will start trading on the Shanghai and Shenzhen stock exchanges.

The aggregate market value of these shares is calculated based on their closing prices on Oct 20, 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.