Stripe’s elevated 65.5% market-implied odds reflect secondary-market pricing that has lifted its valuation from the $159 billion February 2026 tender to roughly $196–199 billion by mid-October, outpacing American Express’s $212 billion public market cap. Traders are weighting Stripe’s 28%+ revenue growth, $2 trillion annual payment volume, and August acquisition of OpenRouter for an estimated $7.5 billion to accelerate AI-agent commerce and stablecoin infrastructure. Amex, trading near $314 per share with a 19x trailing P/E and modest double-digit earnings expansion, offers less near-term upside before December 31. Key catalysts include continued secondary liquidity prints for Stripe and Amex’s upcoming earnings release, which together anchor the current trader consensus on relative valuation trajectories.