Lara Trump served on the board of a company through which the Trump political operation spent nearly $900 million.

Lara Trump, President Trump’s daughter-in-law and a senior campaign adviser, served on the board of a limited liability company through which the Trump political operation has spent nearly $900 million since 2019, according to documents reviewed by The New York Times. She was also named on drafts of the company’s incorporation papers.

The arrangement has never been disclosed. One of the other board members and signatories in the draft papers of the L.L.C., American Made Media Consultants, was John Pence, the nephew of Vice President Mike Pence and a senior Trump adviser. The L.L.C. has been criticized for purposefully obscuring the ultimate destination of hundreds of millions of dollars of spending. Ms. Trump is married to the president’s son Eric Trump.

“Lara Trump and John Pence resigned from the AMMC board in October 2019 to focus solely on their campaign activities. However, there was never any ethical or legal reason why they could not serve on the board in the first place,” said Tim Murtaugh, a spokesman for Mr. Trump. “John and Lara were not compensated by AMMC for their service as board members.”