{"slug": "open-models-lag-closed-models-by-4-months", "title": "Open models lag closed models by 4 months", "summary": "Open-weight AI models now trail proprietary state-of-the-art systems by an average of four months in performance, according to Epoch's internal capability metric. The Epoch Capability Index, which aggregates benchmark results across multiple tasks, shows a consistent lag between the release of closed models and the emergence of open models matching their capability. This gap highlights a persistent competitive disadvantage for open-weight AI development.", "body_md": "Epoch's work is free to use, distribute, and reproduce provided the source and authors are credited under the Creative Commons BY license.\n\n## Learn more about this graph\n\nWe calculate the average amount of time it takes for the best open-weight models to catch up with state-of-the-art performance according to our internal capability metric, the [Epoch Capability Index](https://epoch.ai/eci) (ECI). ECI is a composite measure that captures performance across many benchmarks.\n\n### Analysis\n\n### Limitations\n\n## Explore this data\n\nBenchmark results featuring the performance of leading AI models on challenging tasks.", "url": "https://wpnews.pro/news/open-models-lag-closed-models-by-4-months", "canonical_source": "https://epoch.ai/data-insights/open-closed-eci-gap", "published_at": "2026-05-31 04:02:46+00:00", "updated_at": "2026-05-31 04:15:12.654162+00:00", "lang": "en", "topics": ["artificial-intelligence", "machine-learning", "large-language-models", "ai-research"], "entities": ["Epoch", "Epoch Capability Index"], "alternates": {"html": "https://wpnews.pro/news/open-models-lag-closed-models-by-4-months", "markdown": "https://wpnews.pro/news/open-models-lag-closed-models-by-4-months.md", "text": "https://wpnews.pro/news/open-models-lag-closed-models-by-4-months.txt", "jsonld": "https://wpnews.pro/news/open-models-lag-closed-models-by-4-months.jsonld"}}