Recent post-IPO volatility in SpaceX shares, which comprise over 80% of Musk’s holdings and incorporate xAI’s large language model assets, combined with Tesla’s electric vehicle and autonomous driving performance, drives the tightly contested Polymarket odds around the $700B–$1T range. A June 2026 correction tied to broader AI infrastructure spending concerns and interest rate uncertainty erased hundreds of billions before partial rebounds, leaving traders focused on near-term SPCX and TSLA price action through September 30. Competitive dynamics hinge on whether sustained AI benchmark progress or robotaxi/Optimus milestones lift valuations versus ongoing tech sector rotation or lockup-related sentiment pressures, with the close spread reflecting high sensitivity to daily market moves.