During the financial crisis, a number of financial organizations known as broker-dealers either failed, were acquired, formed bank holding companies, or needed support from parent companies.

"Faced with funding problems during the financial crisis, many broker-dealers sold securities under duress at fire-sale prices - causing collateral problems for other buyers and sellers," said Eric Rosengren, president of the Federal Reserve Bank of Boston, in remarks focused on one lesson of the financial crisis and the unfinished work of preventing future problems.

A key issue "was the over-reliance on short-term wholesale funding," said Rosengren. And a lesson learned was that an important form of short-term wholesale financing - repurchase agreements or repos - "was actually not nearly as stable as many had expected."

Potential runs on large broker-dealers may be difficult to preclude or offset, even if the broker-dealer is in a bank holding company, as many now are. Laws and regulations prevent bank support for affiliated nonbank subsidiaries like broker-dealers, and laws also now limit the government's ability to provide emergency support during crises.

So it is "imperative that preventive measures be taken to ensure that in future crises, broker-dealers' financing mechanisms are robust enough to endure potential financial stress."

Rosengren agrees with other policymakers who have said that a capital charge on short-term wholesale funding would help. And he noted that "much greater disclosure on 'runnable' liabilities could utilize the power of markets to help curb unhealthy levels of reliance on such funding."

On the topic of disclosures, "work has begun to look for opportunities to provide more detail on short-term wholesale funding in bank holding company reports," said Rosengren. "I am hoping that this effort will develop sufficient detail on collateral type and maturity structure so that risks in this market can be better assessed, going forward."