Federal prosecutors in Brooklyn have sought bank records about entities associated with the family company of Jared Kushner, President Trump’s son-in-law and senior adviser, according to four people briefed on the matter.

In recent weeks, prosecutors from the United States attorney’s office in the Eastern District of New York subpoenaed records from Deutsche Bank, the giant German financial institution that has lent hundreds of millions of dollars to the Kushner family real estate business.

Mr. Kushner, who was the Kushner Companies’ chief executive until January, still owns part of the business after selling some of his stake. The family businesses include many legal entities. It is not clear which records were sought by prosecutors, what they are seeking to learn from them or to what degree, if any, they directly involve Mr. Kushner.

There is no indication that the subpoena is related to the investigation being conducted by Robert S. Mueller III, the special counsel, into Russian meddling in the 2016 United States presidential election. Three prosecutors on Mr. Mueller’s team previously worked at the United States attorney’s office in Brooklyn, one as recently as this year. Federal prosecutors around the country typically check with Justice Department headquarters when their investigations may overlap.