Hong Kong's main tech stock index plans to include 20 more companies as well as artificial intelligence and robotics themes to reflect changes in the industry, the firm compiling it has said.

Launched in 2020, the Hang Seng Tech Index tracks the 30 largest tech companies listed in Hong Kong.

The benchmark, which has $40.4 billion in assets tracking it, plans to increase the number of constituents to 50, Hang Seng Indexes Company said in a market consultation document released on Monday.

It plans to overhaul its six tech themes to add artificial intelligence and robotics to the list, which would also include digital platforms, advanced hardware, cloud, and frontier technology.

"As Hong Kong's technology sector continues to broaden, the proposed changes aim to expand technology theme coverage, refine constituent selection, and increase the number of constituents, so the index continues to represent the evolving tech landscape," the company said.

Sub-themes would also be expanded from 16 to 24, including quantum computing and aerospace and satellite technology as new categories.