Deutsche Bank AG received a subpoena earlier in the fall from U.S. special counsel Robert Mueller’s office concerning people or entities affiliated with President Donald Trump, according to a person briefed on the matter.

The subpoena requested documents and data about accounts and other dealings tied to relationships with Mr. Trump and people close to him, the person said. The bank has lent more than $300 million to entities affiliated with Mr. Trump, according to public disclosures.

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