US Stock Market: Heavy short selling puts spotlight on SpaceX's volatile post-IPO journey

Short interest in SpaceX has surged to around 196 million shares, about 31 percent of free float, up from 83 million shares a week earlier following its June 12 IPO debut. The stock fell as much as 23 percent after listing before recovering, leaving short sellers with mark-to-market losses of approximately $760 million. Borrow costs remain low at around 1 percent, and analysts warn a continued recovery could trigger a sharp short-covering rally.