An American company founded by Shervin Pishevar of Uber fame, and former Cisco CEO Robert Loyd. Hyperloop One has received around $250 million investment to date.
They have constructed the so far only working prototype of a Hyperloop system, a 500m long tube and linear induction motor at their facility in Nevada. They have announced a number of feasibility studies with various governments and held the Hyperloop One Global Competition to find promising projects. To date no study appears to have progressed into further stages.