Howie Hubler was right about subprime and still lost $9B — Morgan Stanley's biggest trade

Howie Hubler ran Morgan Stanley's Global Proprietary Credit Group, which bet correctly against $2 billion in subprime mortgage bonds using credit default swaps. Those short positions were expensive to maintain, so Hubler's team sold CDS protection on $16 billion in AAA-rated collateralised debt obligations — essentially selling insurance on the safest-rated bonds — to generate premiums that funded the subprime shorts. The trade seemed intelligent: the subprime shorts would profit if the market fell, and the AAA CDS would be safe because AAA bonds never default.

The AAA-rated CDOs contained the same subprime mortgages that Hubler was shorting. When the housing market collapsed, both legs of the trade failed simultaneously. A stress test in early 2007 showed that at a 10% default rate, a projected $1 billion profit would become a $2.7 billion loss. Hubler disputed counterparty valuations, delaying recognition of the losses and making the position worse. By the time Morgan Stanley's senior management removed him, the group had lost $9 billion — at the time the largest single trading loss in Wall Street history.

Hubler resigned in October 2008 rather than being fired, and received a $10 million departure payment. Morgan Stanley lost $58 billion overall during the 2008 crisis. The case became a textbook example of correlation risk: the assumption that AAA-rated securities were independent of the subprime market was wrong, and the trade that was supposed to be a hedge became a doubling-down.

Sold insurance on $16B AAA CDOs to fund a $2B subprime short, but the CDOs held the same mortgages, so both legs failed together and lost $9B.

Hubler assumed AAA-rated CDOs were independent of the subprime mortgages he was shorting — in reality, they contained the same underlying assets, so his hedge was no hedge at all.

The trade was too large relative to Morgan Stanley's limits — a single trader was allowed $16B in CDS notional on top of a $2B short, creating a concentration risk the bank's risk managers missed.

Hubler disputed counterparty valuations to delay recognising losses, which made the position worse — the bank's management did not intervene until the losses were already catastrophic.

A hedge that assumes AAA-rated bonds are safe while shorting the same mortgages they contain is not a hedge — it is a two-legged bet on the same outcome.