There are sickly European banks. And then there is Deutsche Bank.

Shares of the German banking giant, like those of a number of its peers in Europe, have swooned over the last year as investors reject banking models that rely on volatile market activities as opposed to collecting deposits or managing investor accounts.

The latest turbulence came on Monday. Shares of Deutsche Bank touched new lows after a German magazine reported that Berlin had ruled out providing government aid to Deutsche Bank.

The question of assistance arose after a disclosure by the bank last week that the United States Justice Department, as an opening position, was seeking $14 billion in penalties as part of its investigation of the bank’s underwriting of residential mortgage-backed securities before the financial crisis.

That sum is equal to the bank’s market capitalization, which now stands at $14 billion.

A Deutsche Bank spokesman said on Monday that John Cryan, its chief executive, had “at no point” asked Chancellor Angela Merkel to intervene in the issue with the Justice Department.