They say they are comfortable using Deutsche Bank for such trades because they are certain the German government would never let it fail.

For providing all manner of lending and trading services to hedge funds and other investors, Deutsche Bank is one of the elite practitioners on the street, with large trading hubs in London and New York.

In the parlance of traders, the bank is called “a flow monster,” meaning it makes its money by capturing a piece of the trillions of dollars of bonds and stocks that are the lifeblood of today’s global financial system.

But this status is only as good as the trust that hedge funds and institutional investors have in the bank to make good on trades and to be a sound steward for assets that are parked there.

Making matters worse for Deutsche Bank is that short-term rates tied to the Libor, or the London interbank offered rate — the benchmark financial institutions use when they borrow money — have been edging up as a result of concerns over rising interest rates and a dearth of ready cash in the markets.

Higher rates and worries about the bank’s financial health can be enough for some clients to take their business elsewhere.

“Why would you keep collateral with Deutsche Bank right now?” said Raoul Pal, an independent research provider who has been an outspoken critic of the bank for several years. “If you are a hedge fund right now, you start pulling lines and go somewhere else.”