The Bank of East Asia was recently dropped as a constituent of the Hang Seng Index after having been on the list for more than 30 years.
BEA chairman David Li Kwok-po believes that with mainland companies listing in Hong Kong in increasing numbers, more local constituent companies will be displaced.
I went to a seminar earlier and heard Chinese Association of Hong Kong & Macao Studies president Xu Ze say that mainland firms now make up 60 percent of the local bourse's total market capitalization of over HK$32 trillion.
The proportion is substantially higher than it was 20 years ago, and is the key force that has been boosting the clout of the local market.
There was a time when the aggregate market cap of HSI constituents was only HK$20 billion. Then the state enterprises came, many of them behemoths with market values in the hundreds of billions of dollars.
As a result, only those local blue chips that are "as rich as a country" managed to stay as index constituents.
With the latest listing of a new batch of tech shares, more mega mainland firms have landed here, and Li was right in predicting that more local players would be bowing out.
While many local firms have been overtaken by mainland ones in market value, they maintain their own style in management and in the protection of shareholder interests, and still command the trust and favor of many investors.
Therefore, it has been suggested that a separate "index of Hong Kong enterprises" be established.
But to do so, one has to first define the term "Hong Kong enterprises," which could be tricky as many Hong Kong-capital firms are not registered here for political or tax reasons.
Would the option of using the status of key shareholders as a basis for the definition work?
Perhaps Li may ask BEA's research department to look into this and other related questions.
If the bank helps to bring the index idea to fruition, it would not only provide investors with an extra reference tool, but would be good publicity for the bank too.
Siu Sai-wo is publisher of Sing Tao Daily