It is not really down (obviously) but its price overflowed the range for a 32 bit unsigned integer and so, from what I understand, at least some software has apparently problems to display the price properly.
Yes, various other stories about it. I find it amusing that some finance sites like Yahoo Finance and ETrade (those are the only ones I checked) are correctly displaying the price at 431998 or thereabouts, and some are not. Different APIs in use by the different sites? Or are they special casing all stocks with a share price above 400k? (yeah, there's only one)
I am going to guess that a few weeks back there was a scramble at various brokerages to ensure that they do not allow people to buy BRK.A at an absurdly low price, and it is all a huge mess while they wait on NASDAQ to correct the error.
It wouldn't matter would it? The bot makes a whole lot of $1 bids and finds no sellers, life carries on.
For bots that might want to sell the stock this would likely be a large enough jump to trip a circuit breaker.
But really this was a display bug. It's possible some bot is still using 32 bit unsigned ints internally, but it would have to be pretty badly designed since this issue has been obvious and a long time coming.
Bot behavior under improbable scenarios is a function of its author's paranoia. I'm sure you're right about the vast majority of bots, but I'll be much more amused than surprised if it happens
You don't even actually match up buyers and sellers on the public markets anymore for stocks. Individuals (from retail to institutional investors) buy and sell to market makers; later, when settling, market makers will pair up with brokers when clearing the funds.
So it'd be up to the market makers to not fuck up and sell at $1. If not, it's their liability.
Berkshire Hathaway’s Stock Price vs. 32-Bit Integers - https://news.ycombinator.com/item?id=27065853 - May 2021 (69 comments)