SpaceX's completed June 2026 IPO, which raised $75 billion at a $1.77 trillion valuation and established the largest-ever U.S. debut by proceeds and post-listing market cap, anchors the 94.5% implied probability. Integration of xAI, Starlink revenue growth, and positioning as a combined space-AI platform with multi-trillion-dollar addressable markets further reinforced trader consensus around its scale versus peers. Anthropic's pending late-2026 filing targets a potentially $1 trillion-plus valuation but faces execution and timing hurdles that limit upside relative to SpaceX's realized benchmark. A record Anthropic raise exceeding $90 billion or unexpected OpenAI acceleration could narrow the gap, though current filings and market caps indicate limited realistic paths to overtaking the leader before year-end.