A spokesman for Adelson declined comment.
Adelson sued O'Keeffe in a Hong Kong court after a December 2012 article in The Wall Street Journal described Adelson as "a scrappy, foul-mouthed billionaire from working class Dorchester, Mass."
Adelson took issue with the "foul-mouthed" label and filed suit in Hong Kong, which doesn't have the same press protections as the U.S. The article detailed a legal battle between Adelson and Steve Jacobs, the former CEO of the Las Vegas Sands' Macau operations.
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U.S. Magistrate Judge Mark Falk ruled Tuesday that Adelson could not block efforts by O'Keeffe from seeking documents from Kirk Thorell, a partner in PricewaterhouseCoopers' Florham Park, New Jersey, office, who was Las Vegas Sands Casino's auditor for 25 years.
"It is O'Keeffe's position that Mr. Thorell has or may have information and/or documents that would support the notion that Mr. Adelson is 'foul-mouthed,'" Falk wrote in his opinion.
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In a statement, Jason Conti, senior vice president and deputy general counsel, for Dow Jones, said: "We are gratified that the court rejected Mr. Adelson's attempt to avoid discovery in the United States. We will continue to vigorously defend our reporter in this meritless Hong Kong libel case."
To read the full NJ.com report, click here.