Subject: Re: brkb big block on the open,
I think HC was referring to a big trade by persons unknown, but continuing Jim's thread:

Unless/until P/B starts to mean something meaningfully different as a quick yardstick for value, I see no reason to think that management would purchase a B share at over 1.48 times book (known and published peak-to-date book per share at the beginning of the month in question) in order to add to the value of remaining shares, for the simple reason that they haven't done so.

Which is 1.48 x $303.37 = $449
About 7% down from here.
About 17% down from peak share price.

I'd be surprised if they did repurchase anytime soon, though.
They are in 'batten down the hatches' mode, expecting rough weather.