House Democrats just told the IRS to cough up President Trump’s tax returns and named five companies in particular that they’re interested in. “The five companies are those that really comprise his empire. These are the five corporate entities that he wholly owns that are basically the picture of his financial interests,” Rep. Dan Kildee (D-MI), a member of the House Ways and Means Committee, which requested the documents, told The Daily Beast. So why are each of those companies so intriguing to Congress?

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Personal returns: In addition to tax documents for Trump’s companies, the House Ways and Means Committee wants the president’s personal returns. Trump consistently refused to release his personal income taxes during the 2016 campaign as other presidential candidates had before him, raising questions about what he wanted to keep from the public eye. But if the committee gets the returns, they won’t be made public, Kildee said. “The next step would be the deep dive analysis, which is as painful as the wait for this letter.” The IRS, he noted, is legally required to hold six years of tax returns (though he thought it may be seven). “So we asked for six.”