The Mueller report said WikiLeaks did not receive the hacked DNC emails and documents from GRU officers until July 14 - four days after Rich had been murdered.
"The file-transfer evidence described above and other information uncovered during the investigation discredit WikiLeaks's claims about the source of material that it posted," the Mueller report stated.
During the campaign, in an August 25, 2016 interview with Fox News cited by Mueller, Assange asserted that Rich - who was murdered on July 10, 2016 - was a 'potential' source of emails from inside the Democratic National Committee.
WikiLeaks stuck to that story, even as U.S. investigators began to focus more and more on the ties between Assange and Russian GRU hackers, as WikiLeaks increased the reward for clues to Rich's murder to $130,000 the day before President Donald Trump was inaugurated in January of 2017.
Not only did WikiLeaks push the Seth Rich angle - along with Fox News, Infowars, and various conservative talk radio hosts - but so too did the Russians; this tweet was from the Russian Embassy in London in May of 2017.
Two days after that tweet from the Russian government, former House Speaker Newt Gingrich used an appearance on 'Fox and Friends' to further spread the theory that Rich had been murdered after giving WikiLeaks thousands of hacked documents from the DNC, as the matter quickly gained the attention of talk radio and conservative commentators.
Soon after that Gingrich interview in May of 2017, Fox News retracted the network's original report tying Rich to the leak of materials to WikiLeaks.
In the end, investigators concluded all signs pointed to Moscow and Assange, as the Mueller Report said the mentions of Rich were "designed to obscure the source of the materials that WikiLeaks was releasing," that being the Russians.
Like the Pizzagate conspiracy theory - which claimed that a supporter of Hillary Clinton was running a child sex ring out of a neighborhood pizza parlor in Washington, D.C. - no evidence was ever offered up by Assange and WikiLeaks to support the Rich claim.