That also means that Mueller already knows whether Michael Cohen traveled to Prague in summer 2016 to meet with Kremlin agents while working as Trump's attorney, Schindler said.
CNN reported Wednesday evening that Serhiy Lyovochkin and Rinat Akhmetov were the intended viewers of the data Manafort showed to Konstantin Kilimnik, who has alleged ties to Russian military intelligence.
Legal experts told ABC News this week that sharing campaign polling data with a foreign person is not a crime, but could be an important piece to the puzzle concerning possible Trump campaign coordination with Russians during the 2016 campaign - a subject being investigated by special counsel Robert Mueller's office.
Former Trump campaign manager Paul Manafort departs from U.S. District Court in Washington, U.S., February 28, 2018.
Some Trump critics touted the revelation as the strongest evidence to date of collusion between the Trump campaign and Russian government.
Schindler noted with some irony that Snowden's documents were dumped online by WikiLeaks, which US intelligence says the Kremlin used to promote active measures against Hillary Clinton to help Trump win the election. He entered a plea agreement with special counsel Robert Mueller on September 14, 2018, but prosecutors have since alleged that Manafort has violated the terms of the deal by lying about certain topics.
The New York Times reported that Gates also transferred polling data to Kilimnik in the spring of 2016.