A profile of Chinese bitcoin mining company Bitmain, now allied with Eric Trump's American Bitcoin and previously the target of a DHS espionage-risk probe (Ryan Weeks/Bloomberg)

Ryan Weeks / Bloomberg:
A profile of Chinese bitcoin mining company Bitmain, now allied with Eric Trump's American Bitcoin and previously the target of a DHS espionage-risk probe  —  Bitmain has been dogged for years by questions about the security of its mining rigs.  But that hasn't stopped it from going into business with a key member of the First Family.