Subject: Re: Fractional A Shares
There is no such thing as a true fractional share. It's just the broker buying a whole share and making a book-keeping entry to allocate fractions to customers. The fractional amount that is _not_ held by customers, the broker is on the hook for that.

Financially not a big deal on a $300 stock, but a pretty big deal on a $510,000 stock.
Especially when the customers who want a fractional share of BRK can just buy whole and/or fractional shares of BRK-B.