PetroChina, China Shenhua Energy and China Overseas Land are to join Hong Kong's Hang Seng Index (HSI), the South China Morning Post reported. They will join seven other H-share companies – firms that are listed in Hong Kong but incorporated in mainland China – already on the blue-chip index as the total number of index constituents rises to 43. PetroChina and Shenhua, China's largest oil producer and biggest coal firm respectively, had been widely tipped for inclusion following the HSI's latest quarterly review. Property developer China Overseas Land was a surprise choice, with Aluminum Corp of China (also known as Chalco) or China Cosco Holdings thought to be more worthy of inclusion. PetroChina's weighting will be 5.84%, the third-heaviest in the HSI after China Mobile and HSBC Holdings. Shenhua has a 2.39% weighting and China Overseas Land 1.07%. The changes will take effect December 10.