Pardon my ignorance, Alex, but how does a CDS work? And what happens when it doesn't work?
A CDS is basically a bet on whether a company's bonds (debt) defaults of not. In simple terms it is insurance against defaults. Originally it was designed so that I can protect myself against the default of a loan I've made to a company. But these days you can make a bet on debt you don't own.
So if say I am short (selling) a General Motors CDS and you are long (buying). You pay me an amount for the swap (think of it as an insurance premium). If General Motors debt defaults, I pay you.
Like any other instrument, the price depends on market perception. So if people think the chance of default are very low, the price of the swap will be very low. i.e. it costs very little to 'insure' a default. But what happens when defaults rise (if we have a recession, for example) above what people thought? The people who are 'short' the CDS will have to pay up, big time. Who is short the CDS's? Who knows. They're generally OTC (over the counter) instruments, as opposed to being trackable through a central exchange.
It sounds complex but it boils down to this: people mispriced risk. They thought the mortgage backed CDOs were safer than they were, so they priced them too low, so when mortgages started defaulting they took losses. CDS will be a similar sort of thing for corporate debt. High yield (junk) debt default rates have been at historic lows. And junk debt issuance (some companies need to keep issuing new bonds to make interest payments) has been frozen for months. What happens when companies that have issued junk bonds start defaulting?
The other issue is what happens if, say, the party on the short end who has to pay up doesn't have the money? It might be a hedge fund. They would have to sell other stuff in their portfolio, and drag markets down.
Alex