**Anthropic's pursuit of a roughly $2 trillion IPO valuation, supported by its $65 billion annualized revenue run rate and projections exceeding $110 billion by year-end, underpins the narrow lead in trader-implied odds over SpaceX.** SpaceX completed the largest IPO to date in June 2026, raising $75 billion at a $1.77 trillion valuation and trading near $2 trillion recently, yet Anthropic's confidential S-1 filing and Nasdaq listing plans for November position it to exceed that benchmark if executed. xAI's February merger into SpaceX eliminates it as a standalone contender, while other candidates trail far behind. The tight contest reflects uncertainty around Anthropic's final pricing amid high infrastructure costs and revenue multiples near 18x, versus SpaceX's proven Starlink cash flows offset by AI integration expenses. Key catalysts include Anthropic's roadshow timing and any revisions to its $2 trillion target.