Australian billionaire Anthony Pratt, with whom Trump allegedly shared nuclear secrets, is permanently moving to the U.S.

“Honoured to be granted my Green Card for permanent USA residency last month,” Pratt said in a LinkedIn post on Sunday.

The “cardboard king” and chairman of privately-owned paper and packaging plants Visy and Pratt Industries said he’s invested in 70 U.S. factories providing 12,000 jobs over the past 30 years. Pratt’s family is also all U.S. citizens. He will make frequent trips to his home country, where he remains at the helm of Visy Australia.

Pratt’s move coincides with Donald Trump’s return to the White House, which snowballed the wealth of billionaires in a post-election stock surge. Pratt, who is worth $12.3 billion according to the Bloomberg Billionaire Index, was no exception, becoming $311 million wealthier the day after Trump’s win. 

But Pratt and Trump’s relationship spans far deeper than just wealth. Trump allegedly spilled potentially sensitive information about U.S. nuclear submarines to the Australian mogul, who in turn shared the secrets with dozens of other people, including journalists and foreign officials, ABC News reported in October 2023. The information, reportedly shared at the Mar-a-Lago country club, allegedly included the exact number of nuclear warheads routinely carried by submarines, as well as the distance the submersibles can maintain to go undetected by Russian submarines. Pratt has been a member of Trump’s Mar-a-Lago Club since 2017, 

Trump allegedly took highly sensitive information after he left the White House in 2021, stashing it in his Mar-a-Lago home and showing it to officials not authorized to view them. The Justice Department indicted Trump on 40 felony counts, including 32 counts of “willful retention” of government documents under the Espionage Act—all of which are likely to disappear following Trump’s inauguration. Prosecutors identified Pratt and 80 others as potential witnesses to testify against Trump at his classified-documents trial.

Trump and Pratt did not immediately respond to Fortune‘s requests for comment.

Relationship status: It’s complicated

Trump’s goodwill for Pratt faltered shortly after the investigations revealing Pratt’s alleged knowledge of government secrets. The former president vehemently denied sharing information with Pratt, calling him “a red haired weirdo from Australia” in a post on his social-media platform Truth Social.

But Pratt has about a decade of rapport with Trump that helped launch him to insider status, having supported him since at least the aftermath of the 2016 election. The paper magnate promised in 2017 to invest $2 billion in U.S. manufacturing jobs, predominantly in the Midwest. Pratt broke ground on a $500 million Kentucky box plant and paper mill in 2021. 

“We made a pledge to invest $2 billion in America to create 5,000 high-paying manufacturing jobs, mainly in the Midwest,” Pratt told Bloomberg in December 2019. “That was music to President Trump’s ears.”

Donald Trump, Anthony Pratt, and Australian Prime Minister Scott Morrison touring the the Wapakoneta, Ohio paper plant during its opening in 2019.

SAUL LOEB/AFP—Getty Images

In a tit-for-tat, Trump’s corporate tax cuts in 2017 helped make Pratt $2 billion richer. The same year, Pratt started taking out full-page ads in the Wall Street Journal, thanking the Trump administration for supporting U.S. manufacturing. The goodwill continued ahead of the 2020 election when Pratt reportedly offered to help Trump host his election party at his country club.

“If Potus is having his election party at mar Lago I’ll book as many rooms as available,” Pratt told a colleague in a message seen by federal investigators, according to a New York Times investigation. “Reasons he should [are] 1 it will shore up the Florida electoral college 2 it will be good for business.”

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