The 204-day gap between Claude Opus 4.5's release and GLM-5.2's release confirms the commonly cited 6-9 month performance lag between U.S. closed labs and Chinese open-weight labs.

Calculating the exact time gap between Opus 4.5 and GLM-5.2 (204 days, ~6.8 months), the author finds it lines up precisely with the widely claimed 6-9 month open-closed capability lag. ✦ AI generated

Nathan Lambert · Interconnects · 2026-06-22 · original ↗

With Claude Opus 4.5's release on November 24th, 2025, the gap in time to GLM-5.2's release on June 16th, 2026 is 204 days — or about 6.8 months. This puts us square in the 6-9 month time gap that many people claim as the performance lag between the U.S.'s closed labs and China's open counterparts.

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