OpenAI releases GPT-5.5 and GPT-5.5 Pro via API, markets hit ceiling

OpenAI announced GPT-5.5 and GPT-5.5 Pro are now available through its API. The market for GPT-5.5 release by June 30, 2026, sits at 100.0% YES, confirming a certain resolution.

Market reaction

GPT-5.5’s release has pushed all related markets to their ceilings. The April 30, 2026 market is at 100.0% YES, up from 98% just 24 hours ago. The April 23, 2026 market jumped to 100.0% YES from 93% a day earlier.

The June 30 contract has $20,466 in actual USDC traded daily. The April 30 contract, now just days from expiry, has $30,936 in actual USDC daily volume. The largest price move in the last 24 hours was a 3-point drop at 5:37 PM, likely an overreaction to interim updates.

Why it matters

This announcement ends speculation and locks in payouts for YES holders. With a YES share priced at 100¢, there’s no upside left. The question now is how GPT-5.5’s capabilities affect other AI markets, particularly those tracking competitors like Claude 5.

What to watch

Traders should monitor any new technical details or performance benchmarks that could move related AI markets. Sam Altman or OpenAI announcements on future models could drive new contract activity.

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