Vivek Ramaswamy, the Republican presidential candidate who made a fortune in biotech, once was involved in a significant investment in a biotech company run by disgraced investor Martin Shkreli.

Shkreli, the oft-described “pharma bro” who went to prison for four years for committing securities fraud and securities fraud conspiracy after he gained notoriety for dramatically raising the cost of a life-saving antiparasitic drug, said in a YouTube video in mid-April that Ramaswamy was at one point his “biggest investor” and called him “a friend.”

“He basically took our business model and supersized it,” he told the “My First Million” podcast in a little-noticed part of the video. “Who influenced who is a matter that is left to history.”