(Bloomberg) -- Democratic lawmakers are increasingly demanding that U.S. authorities investigate allegations raised in a recent magazine article that traders might be using non-public government information to reap huge illegal profits, even as the exchange where the transactions purportedly took place called the story “patently false.”

In a Monday letter, 14 Democratic senators urged the heads of the Justice Department, FBI, Commodity Futures Trading Commission and Securities and Exchange Commission to probe “disturbing reports of suspicious trading in our futures and equities markets” described in a Vanity Fair piece. The magazine referred to the transactions as “Trump Chaos Trades.”

Since the story’s publication, the suggestion that White House leaks could be a factor in futures traders making billions of dollars from well-timed bets ahead of major geopolitical announcements has fueled endless chatter from Washington to Wall Street. Still, the article has been met with widespread skepticism from the financial industry.

CME Group Inc., the world’s biggest futures exchange, has dismissed the claims, arguing that the trades highlighted in the story couldn’t have been based on inside information because too many market participants were involved. The article describes five big transactions in S&P 500 e-mini futures from June 28 to Sept. 13, ranging from 55,000 to 420,000 contracts.

“As it relates to the Vanity Fair article published on October 17, 2019, regarding activities in the E-mini S&P futures contract, the allegations about the trading activity are patently false,” CME said in an Oct. 18 statement.

In Monday’s letter, Democrats said they wanted federal authorities “to investigate immediately whether any rules, laws or regulations were violated.” The lawmakers added that “if any wrongdoing is uncovered, we demand that you swiftly hold violators accountable to the fullest extent possible.”

Spokesmen for the SEC and Justice Department declined to comment, while spokesmen for the FBI and CFTC didn’t immediately respond to requests for comment.

The wagers cited by Vanity Fair were made shortly before market-moving news -- three times involving the U.S.-China trade war, once involving the bombing of Saudi oil fields and once involving Hong Kong politics. Thanks to market reactions, the magazine said, people involved in the transactions could’ve booked gains of between $82.5 million on the smallest to $1.8 billion on the biggest.

The story’s author, William D. Cohan, has said that finance professionals with decades of experience alerted him to the trades. Cohan, a former Bloomberg Opinion columnist, has said that factors other than illegal buying-and-selling could explain the transactions and that he doesn’t know whether any nefarious activity actually occurred.

Earlier Monday, Angus King, an independent Maine senator who caucuses with the Democrats, also called on the SEC to investigate. Last week, Democratic Representatives Ted Lieu and Kathleen Rice requested a federal investigation into the timing around sales of e-mini futures contracts before significant geopolitical events or statements from Trump.

--With assistance from Nick Baker.

To contact the reporters on this story: Ben Bain in Washington at bbain2@bloomberg.net;Matt Robinson in New York at mrobinson55@bloomberg.net

To contact the editors responsible for this story: Jesse Westbrook at jwestbrook1@bloomberg.net, Gregory Mott

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