The SpaceX and OpenAI IPOs Are Imminent. History Says the Stocks Will Do This When They Start Trading.

SpaceX and OpenAI are reportedly targeting IPOs in 2026, with implied valuations of about $1.25 trillion and $852 billion, respectively, making them potential record-setting U.S. listings. The article argues both would debut at very rich price-to-sales multiples of roughly 69x and 65x, and cites historical data showing the 10 largest IPOs underperformed by a median 11% in the first 3 months and 26% in the first year. The message to investors is cautious: large IPOs have often been poor buy-on-day-one long-term investments.

Analysis

The key market implication is not the IPO itself but the implied cash-flow benchmark it sets for the entire private-market AI stack. If the market starts pricing 60x+ sales for late-stage frontier AI and space infra, that raises the bar for every adjacent private company still funding at heroic multiples, and it compresses the runway for second-tier names that need public comparables to validate their own marks. The first-order winners are likely indexable platforms and infrastructure vendors that can harvest the attention cycle without bearing the execution risk; the losers are companies with similar narrative profiles but weaker growth durability or lower capital efficiency.

The more important trading window is the post-lockup/first-earnings phase, not day one. Large, attention-rich IPOs often see a reflexive pop on scarcity and passive demand, but that flow tends to reverse once secondary supply expands and investors begin underwriting quarter-to-quarter margin structure instead of TAM storytelling. If these companies come public into a risk-on tape, the initial move could be mechanically strong; the higher-probability edge is fading strength after the first 4-12 weeks, especially if guidance implies heavy reinvestment and profitability remains distant.

For public comps, this is mildly supportive for sentiment around AI leaders but not necessarily for the crowded retail-owned names. PLTR can benefit from a higher sector multiple ceiling, but its own valuation leaves little room for further rerating unless fundamentals reaccelerate meaningfully. UBER and CPNG are the cleaner contrast trades: both are exposed to the market rotating capital away from 'story premium' toward businesses where earnings visibility is better and valuation is less fragile. UPS and T are low-beta beneficiaries only insofar as investors seek quality balance sheets if the IPO window turns into a speculative air pocket.

Consensus may be missing that the real risk is not overvaluation alone, but supply shock from a successful listing cadence. If several mega-cap private names come out in 2026, they will compete for the same marginal growth capital and index inclusion dollars, which can pressure late-stage private rounds and secondary shares even before the IPOs begin trading. That dynamic argues for caution on the most crowded AI beta and for using any headline-driven enthusiasm to buy cash-generative names with lower duration risk.