Deutsche Bank has received a subpoena from the US special counsel investigating possible collusion between President Donald Trump’s campaign and Russia. It's actually welcome news for the bank.

Two flags, one subpoena. Deutsche Bank may be glad it's being forced to hand over information.

Deutsche Bank has been served. US investigators are demanding that it provide information on dealings linked to the Trumps, sources familiar with the matter told Handelsblatt. The subpoena is part of a probe by special counsel Robert Mueller and his team to determine whether the president’s campaign was involved in Russian efforts to influence the US election.

Donald Trump and his family have long-standing ties to Germany’s largest bank. The former real-estate baron has done billions of dollars' worth of business with Deutsche Bank over the past two decades, and First Lady Melania, daughter Ivanka and son-in-law Jared Kushner are also clients.

According to media reports, Mr. Trump owed Deutsche Bank as much as $340 million (€286.5 million) at one point, though considerable restructuring appears to have brought down that amount. The president’s financial disclosure of June 16 reported $130 million in debt, a figure the bank has not publicly confirmed.

It remains unclear whether Mr. Mueller requested information on President Trump’s own business dealings with Deutsche Bank or on those of people close to him. Sources told Handelsblatt that the US Justice Department has already received some records from the bank.

Deutsche Bank apparently received the subpoena weeks ago, but a spokesman said the bank would not comment on individual cases “out of respect for investigating authorities” and for legal reasons. The bank regularly cooperates with agencies in every country, the spokesman added.

For months now, Deutsche Bank has been a focus for Trump’s critics.

Handing over the records now could actually help Deutsche Bank emerge from the shadows cast by its problematic clients. While banks are normally proud to cater to heads of state - London's Coutts is famous for its relationship with Queen Elizabeth II - the Trumps have proven to be more of a liability than an asset. As one manager told Handelsblatt this summer, Deutsche Bank’s ties to Trump pose an “enormous reputational risk.” Executives in Frankfurt have been bracing for difficult times ahead in Washington, with the bank being “led round the political arena by the nose.”

For months now, Deutsche Bank has been a focus for Trump’s critics, who are keen to learn whether any of the president’s business dealings at home and abroad involve the Russian government. In recent months, the bank has denied multiple requests by US lawmakers for information, citing client privacy. But an internal investigation into Mr. Trump’s business dealings has yet to turn up any evidence of problematic ties to Russia.

Yet with Mr. Mueller’s subpoena, Deutsche Bank has no choice but to hand over records associated with the Trump clan, lest it be held in contempt of court. For the bank, it’s a chance to move past its Trump troubles and away from protracted political battles. It should come as little surprise, then, that some in Deutsche Bank’s executive suite actually wanted the special counsel to serve them. They certainly saw it coming: Observers had been speculating since the summer that Mr. Mueller would eventually call on Deutsche Bank.

There’s ample incentive for the bank to act quickly, particularly as the special counsel’s investigation appears to be heating up. On Friday, President Trump’s former national security advisor, Michael Flynn, pleaded guilty to lying to the FBI in January about meetings with Russia’s ambassador to the US, Sergey Kislyak. Mr. Flynn also made it known that he is cooperating with investigators, a potentially worrisome development for Mr. Trump’s team. Multiple US media outlets cited sources who said Mr. Kushner, the president’s son-in-law, had instructed Mr. Flynn to contact the Russian diplomat.

Deutsche Bank is eager to avoid becoming further embroiled in Mr. Mueller’s investigation. After all, the bank is facing its own problems over business dealings in Russia. Regulators there and in Germany, the UK, and the US, have faulted the bank for lax enforcement of anti-money laundering controls, in light of a series of transfers of Russian money to foreign accounts. While it has yet to resolve the matter with the US Justice Department, Deutsche Bank agreed to pay New York’s Department of Financial Services more than $400 million (€337 million) and hire an independent monitor for a two-year period. The bank has also reached a settlement with Britain’s Financial Conduct Authority for a £163 million (€184 million) penalty.

Many of Mr. Trump’s critics believe there might be more to the story and ultimately worry that the president could make sure regulators go easy on the bank. A letter to Deutsche Bank from the Finance Committee of the House of Representatives, led by ranking Democrat Maxine Waters, further fueled suspicions of a connection between Mr. Trump and the bank’s Russian money-laundering scandal. No such connection has been proven. But it's clear nonetheless that the US president will continue to create headaches for Deutsche Bank.

Yasmin Osman, Michael Maisch and Daniel Schäfer reported this story for Handelsblatt from Frankfurt. Astrid Dörner reported from New York City. Amanda Price in New York City adapted this article for Handelsblatt Global. To contact the authors: [email protected], [email protected], [email protected], [email protected].