Judo Capital (JDO) -40.4% today, its worst day ever. Is this contained or does it spread to the other banks?

Profit downgrade on a spike up in bad loans, 3 customers across different sectors deteriorating at the same time apparently. 40% gone in one session — that's not a correction, that's the market questioning the entire business model.

NAB copped the contagion hardest, -3.4%, given it's got the most business lending exposure of the Big Four. ANZ, WBC and CBA all red too, just less brutal. (CBA briefly went green)

Im genuinely split on this one. Judo's a tiny challenger bank with a totally different loan book and risk profile to the majors — arguably this shouldn't spread. But "arguably shouldn't" is also what people said before contagion has spread plenty of times before.

NAB's chart looks awful

Is NAB's move just sympathy selling that fades, or is there real read-through risk here?