Ann: HKEx Monthly Return Notice December 2019, page-8

Yancoal is a very unusual stock.It is a $3.8 billion company but often only $20,000 or so of stock changes hands in a days trade. This is because 94.2 per cent Yancoal is owned by 5 investors (4 Chinese investors and Glencore). These investors never trade their Yancoal shares. So trading is dominated by "mum and dad" investors owning very small parcels of stock. Also,if you look at the market depth, there is typically a very small number of buyers and a very small number of sellers. That is, the market in Yancoal shares is very illiquid. Consequently, there can be large swings in the share price.

I think that once Yancoal starts paying a full franked dividend this could attract greater investor interest. This can't be far away.