But the June stock sale would have coincided with a point when Trump was pouring money into his presidential campaign. During the Republican primary, Trump loaned his campaign US$47m of his own money. In June, as the general election began, he formally forgave the loan and began making cash infusions to his campaign, first donating US$2m on June 22.
Trump then gave US$2m a month between July and August before donating US$10m in October. Much of Trump's campaign was ultimately funded by other donors. In all, Trump gave his campaign US$66m, federal filings show - short of the US$100m that he repeatedly claimed he was spending on his race.
Miller, the Trump spokesman, told The Post about Trump's stock sale Tuesday morning, following Trump's criticism of aviation giant Boeing.
Trump tweeted that Boeing's federal contract to build new Air Force One jets should be cancelled because costs had gone "out of control." Trump was once a company shareholder, tweeting in January 2013 that "@Boeing stock went way down because of 787- so I just bought stock in @Boeing- great company!"
Trump reported owning between US$50,000 and US$100,000 of Boeing stock in the May filing. In the three years between Trump's original tweet about buying Boeing stock and June 2016, Boeing's share price climbed about 70 per cent.
Trump has tweeted that he will separate from his own business, the Trump Organization, but has provided no additional details other than promising to hold a press event on December 15 to outline his plans.
Trump told Fox Business News in August that he was dumping stocks because he predicted the market was crashing, saying, "I did invest, and I got out, and it was actually very good timing." Despite Trump's August comments, stock prices have generally been on the rise since June.
Trump spokeswoman Hope Hicks told The Post last month that Trump had in June also sold his shares in Energy Transfer Partners, the majority stakeholder in the US$3.7 billion Dakota Access pipeline project that has drawn protests from environmentalists and Native Americans.
The Department of the Army said Sunday it would not allow the oil pipeline to be drilled further near a Standing Rock Sioux reservation, but Trump has said he supported completing the pipeline. The company's chief executive was a major campaign donor to Trump, but its stock had declined in value in the face of protests.
Trump said in a financial filing released in May 2015 that he owned between US$500,000 and US$1m worth of stock in Energy Transfer Partners. By May 2016, when Trump updated his annual filing, the value of the holding had fallen to less than US$50,000.
Norm Eisen, who served as ethics counselor to President Obama and has criticized Trump over his conflicts, said it would be "absolutely a step in the right direction" if Trump had sold his stock holdings in June, divesting himself of ownership in companies whose fates could be tied to his policies. But he added that it is now important to know how Trump spent the money he earned from the sale.
"We need to know, has he put them in conflict free assets ... or has he bought other stocks or assets that would create new conflicts?" he asked. "It's all the more reason that we need a prompt and full disclosure financial disclosure. If he did liquidate all his stocks, what did he do with the money? What bank is the money in? What did he buy? It's a lot of money."
He called this the latest example of the tension between Trump's promise to drain the swamp and how he has managed his own business conflicts. "The swamp draining should begin with Trump's own wetlands," Eisen said.
