That relationship turned sour in 2014, though, when Deripaska's representatives filed legal complaints in the Cayman Islands alleging that Manafort all but disappeared with $19 million Deripaska had given him to invest in a Ukrainian TV company called Black Sea Cable.
"Early in the 2016 presidential campaign, Deripaska's representatives openly accused Manafort of fraud and pledged to recover the money from him," the AP reported. "After Trump earned the nomination, Deripaska's representatives said they would no longer discuss the case."
In a July 2016 email, Manafort asked his longtime employee Konstantin Kilimnik, a Russian-Ukrainian dual citizen, to offer Deripaska "private briefings" about the campaign.
Though the filing doesn't name Kilimnik, it says that "Manafort, Gates, and a Russian national - who is a longstanding employee of Davis Manafort Partners, Inc. and DMP International LLC (collectively DMI) - served as the beneficial owners and signatories" on the many offshore accounts they had opened.
"More than $75 million flowed through these overseas accounts," the filing said, "and the government has substantial documentary evidence to support that allegation."
Manafort also "represented the value of his assets on loan applications and other financial documents in divergent amounts, " the court filing says. The values varied wildly in 2016 - $48 million in February, to $136 million in May, to $25 million in November - suggesting "considerable resources, the full extent of which is unclear," the filing says.
Prosecutors say that Gates, meanwhile, "frequently changed banks and opened and closed bank accounts" and that from late 2004 to early 2017 he opened 55 accounts with 13 different banks, some of which were based in England and Cyprus.