Federal records indicate that a key adviser to President Trump held substantial investments in 18 companies when he joined Trump in meetings with their CEOs.

The investments of Christopher Liddell, the president's director of strategic initiatives, totaled between $3 million and $4 million. Among the companies in Liddell's portfolio, and whose CEOs were in the meetings: Dell Technologies, Dow Chemical, Johnson & Johnson, JPMorgan Chase, Lockheed Martin and Wal-Mart.

When Trump conferred with the chiefs of Ford, General Motors and Fiat-Chrysler last month, Liddell attended the session. He was invested in all three companies at the time.

Details of Liddell's investments are contained in documents he filed with the White House ethics officer in preparation for divesting his holdings. He was seeking certificates of divestiture, which allow federal appointees to defer paying capital-gains taxes by reinvesting in a blind trust or similar arrangement.

The watchdog group Citizens for Responsibility and Ethics in Washington filed a complaint Tuesday with White House Counsel Donald McGahn, raising concerns that Liddell may have violated the federal conflict of interest law, a criminal statute.

The complaint states: "If Mr. Liddell personally participated in meetings with companies in which he held significant amounts of stock, he may have violated these rules."

The White House responded with this statement: "Mr. Liddell has been working with the Office of the White House Counsel to ensure he is fully compliant with his legal and ethical obligations in connection with his holdings and his duties in the White House."

Liddell was born in New Zealand and is a U.S. citizen. In the past he has worked as chief financial officer of Ford Motors, International Paper and Microsoft.

It's not clear whether Liddell now has sold off his investments, but he apparently had not done so before the meetings in question. The meetings were held on Jan. 23, Jan. 24 and Feb. 3. On Feb. 9, the Office of Government Ethics issued four certificates of divestiture for Liddell and his wife. They would be worthless if the assets had already been sold.

The complaint is one of several actions by CREW on White House ethics issues. The group says in a lawsuit that Trump is violating the Constitution's ban on foreign emoluments (gifts); it has questioned the ethics of presidential counselor Kellyanne Conway after she urged TV viewers to buy Ivanka Trump's fashion merchandise; and it challenged the lack of transparency of two White House advisory committees.

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