The Hong Kong Exchanges and Clearing flag, China's national flag and the Hong Kong flag outside the exchange. Photo: Reuters/Bobby Yip

Hang Seng Indexes released on Thursday details regarding a long-awaited change to the composition of its China Enterprises Index, which tracks domestic Chinese firms.

The companies to be added include Red chips, stocks of mainland companies incorporated offshore with a minimum of 30% of their shareholding held by mainland entities, as well as P-chips, which are non-state Chinese firms which derive more than 50% of their income from mainland China.

The phase-in of 10 total Red chip and P-chip shares will begin in March of next year with inclusion that represents 2% of the market capitalization of the index:

Source: Hang Seng Indexes