His boxes

Starting in the early months of his administration, Mr. Trump began using a cardboard box to bring papers and documents from the West Wing up to the residence at the end of the day.

In the White House, according to two people familiar with the practice, Mr. Trump was generally able to identify what was in the boxes most immediately around him. One of those people said he was “meticulous” in putting things in specific boxes.

[...]

Shortly after John F. Kelly took over as Mr. Trump’s chief of staff in July 2017, Mr. Kelly and other aides grew concerned that some documents were likely presidential records and might go missing if they were kept in the residence. They impressed upon Mr. Trump that the papers had to be tracked, but he was not especially interested, the people said.

Aides started examining the boxes to check for presidential records, but Mr. Trump still found ways to bring items to the residence. And the boxes began to multiply.

He could point to specific boxes that he wanted to take with him on Air Force One when he was traveling, and decline to take others, appearing aware of the contents inside the boxes he chose.

[...]

Some aides would periodically encourage him to condense the number he had in his immediate vicinity. Another person familiar with Mr. Trump’s habits said that when one box filled up, aides over the past two years would take it away and store it, bringing him a new one.

[...]

On two occasions after he left office — once in late 2021 as he was reluctantly responding to demands from the National Archives to return the material he had taken from the White House and then later after a grand jury subpoena demanding the return of any classified documents still in his possession — Mr. Trump was brought a number of boxes to review, indicating that he was aware of their contents. Mr. Trump repeatedly told advisers the boxes of documents were “mine,” according to several people familiar with his remarks.

  NYT

He packed them. So, they're his.

...but hey, do what you want...you will anyway.