Hang Seng China Enterprises Index is a stock market index of The Stock Exchange of Hong Kong for H share, red chip, and P chip. H share is a class of ordinary share of the mainland China incorporated company that only traded outside the mainland China; all of these companies were majority owned by the central or regional Chinese government. In contrast, civilian-run enterprises of the mainland China listed their companies in Hong Kong using "foreign"-incorporated holding companies as P chip; those using the same method but majority owned by the central or regional Chinese government, was known as red chip; red chip had their own separated index. In August 2017, it was announced that the index would be reformed, which P chip and red chip would be added to the index in March 2018. Some of the constituents of Hang Seng China Enterprises Index was also the constituents of Hang Seng Index. Wikipedia