Ann: Quarterly Activities Report and Appendix 5B - September 2021, page-24

The SOI is not a concern in itself. It just depends on how tightly those issued shares are held. All else being equal, a company with 5 billion SOI where majority of the shares are tightly held will trade better than a company with 500 million SOI in the hands of uncommitted holders.

However a high number of SOI normally implies that a company has gone through several dilutive cap raises and this becomes an issue when those additional shares end up in loose hands. I believe this is the issue which BRK has been facing at the moment. The institutions who participated in capital raisings are happy to flip their shares and free options for a few pips and hence the constant sell pressure.