# Epoch AI describes tracking the ECI leaderboard [Canonical reading](https://escapemeridian.com/readings/epoch-ai-describes-tracking-the-eci-leaderboard-893eeff2) Epoch AI’s page, published July 2, 2026, describes tracking which model has the highest ECI over time and how long it remains at the top of the leaderboard. Epoch AI says ECI can fluctuate slightly, though rarely enough to significantly shuffle model rankings. The page cautions that this retrospective view does not account for changes to ECI estimates since models’ release dates. That leaves an important boundary on what the leaderboard history can show: it reflects the estimates used in the retrospective, not later changes to those estimates. How would incorporating changes to ECI estimates since release affect the reported leaderboard history? Headline and summary by Escape Meridian, prepared by Luna from the attributed source. A source check is not independent confirmation of the source’s claims. ## Original source Epoch AI · Article Original source date: Jul 2, 2026 (2026-07-02T00:00:00.000Z). Date basis: Date supplied by the publisher’s feed. Added to Escape Meridian: 2026-11-06T10:03:24.680Z. First observed: 2026-10-18T03:11:21.935Z. Retrieved: 2026-10-24T03:29:36.578Z. - [GPT-4 led in ECI far longer than any other model](https://epoch.ai/data-insights/gpt-4-longest-eci-lead) ## Limits Text as retrieved on October 24, 2026; originally published July 2, 2026. The retrieved page text describes Epoch AI’s tracking method and limitations, but does not provide the leaderboard data or identify the models and durations behind the source title. ## Open question How would incorporating changes to ECI estimates since release affect the reported leaderboard history? ## Source-stated Epoch AI says it tracks which model has the highest ECI at each point in time and how long the model stays at the top of the leaderboard. > We track which model has the highest ECI at each point in time, and how long it stays at the top of the leaderboard. - [Supporting source](https://epoch.ai/data-insights/gpt-4-longest-eci-lead) ## Source-stated Epoch AI says ECI can fluctuate slightly, though rarely enough to significantly shuffle model rankings. > The ECI can fluctuate slightly over time, though rarely enough to significantly shuffle model rankings. - [Supporting source](https://epoch.ai/data-insights/gpt-4-longest-eci-lead) ## Source-stated Epoch AI says its retrospective view does not account for changes to ECI estimates since models’ release dates. > That said, this is a retrospective view and does not account for changes to ECI estimates since models’ release dates. - [Supporting source](https://epoch.ai/data-insights/gpt-4-longest-eci-lead) ## Source and contributor context Epoch AI · Publisher The publisher is identified here. No individual author has been inferred. ## Source media Media retrieval status: unchecked. ## Terms and references Reference context selected by Escape Meridian; separate from source evidence. Entity mentions do not establish authorship, involvement or endorsement. ## Epoch AI Epoch AI studies trends in AI capability, training resources and the infrastructure behind them. - [Explore this context](/entities/epoch-ai) - [Reference](https://epoch.ai/) - [Reference](https://epoch.ai/data) ## TIME TIME is a news magazine publishing reporting on world affairs, business, technology and the workers behind digital services. - [Explore this context](/entities/time) - [Reference](https://time.com/) ## Editorial provenance Version 1. Publication ID: 460fe918-cf63-0c54-381d-ed2fa70a002e. Prepared by openai/gpt-6-luna; grounding review by anthropic/claude-opus-5.5. Source check: uncertain by anthropic/claude-opus-5.5 on 2026-11-06T09:58:26.384Z. This checks fidelity to the source, not whether its claims are independently true. Editorial selection: accept; reasons: bridge\_admitted\_by\_model, second\_opinion\_categorical. Observation: 5cfcbf0057dcf68bc62569cef7fda0e9505fb80838e31b23cf4160001bacdf35. Source text hash: a022a6dde07c8b64367431e1374b846a074953ee8cdab4b3fc99693bb6c48d9d. ## Revision and source-check history ### Version 1 — 2026-11-06T10:03:24.680Z Epoch AI’s page, published July 2, 2026, describes tracking which model has the highest ECI over time and how long it remains at the top of the leaderboard. Epoch AI says ECI can fluctuate slightly, though rarely enough to significantly shuffle model rankings. The page cautions that this retrospective view does not account for changes to ECI estimates since models’ release dates. That leaves an important boundary on what the leaderboard history can show: it reflects the estimates used in the retrospective, not later changes to those estimates. How would incorporating changes to ECI estimates since release affect the reported leaderboard history? ## Original source Epoch AI · Article Original source date: Jul 2, 2026 (2026-07-02T00:00:00.000Z). Date basis: Date supplied by the publisher’s feed. Added to Escape Meridian: 2026-11-06T10:03:24.680Z. First observed: 2026-10-18T03:11:21.935Z. Retrieved: 2026-10-24T03:29:36.578Z. - [GPT-4 led in ECI far longer than any other model](https://epoch.ai/data-insights/gpt-4-longest-eci-lead) ## Limits Text as retrieved on October 24, 2026; originally published July 2, 2026. The retrieved page text describes Epoch AI’s tracking method and limitations, but does not provide the leaderboard data or identify the models and durations behind the source title. ## Open question How would incorporating changes to ECI estimates since release affect the reported leaderboard history? ## Source-stated Epoch AI says it tracks which model has the highest ECI at each point in time and how long the model stays at the top of the leaderboard. > We track which model has the highest ECI at each point in time, and how long it stays at the top of the leaderboard. - [Supporting source](https://epoch.ai/data-insights/gpt-4-longest-eci-lead) ## Source-stated Epoch AI says ECI can fluctuate slightly, though rarely enough to significantly shuffle model rankings. > The ECI can fluctuate slightly over time, though rarely enough to significantly shuffle model rankings. - [Supporting source](https://epoch.ai/data-insights/gpt-4-longest-eci-lead) ## Source-stated Epoch AI says its retrospective view does not account for changes to ECI estimates since models’ release dates. > That said, this is a retrospective view and does not account for changes to ECI estimates since models’ release dates. - [Supporting source](https://epoch.ai/data-insights/gpt-4-longest-eci-lead) ## Source and contributor context Epoch AI · Publisher The publisher is identified here. No individual author has been inferred. ## Source media Media retrieval status: unchecked. ## Terms and references Reference context selected by Escape Meridian; separate from source evidence. Entity mentions do not establish authorship, involvement or endorsement. ## Epoch AI Epoch AI studies trends in AI capability, training resources and the infrastructure behind them. - [Explore this context](/entities/epoch-ai) - [Reference](https://epoch.ai/) - [Reference](https://epoch.ai/data) ## TIME TIME is a news magazine publishing reporting on world affairs, business, technology and the workers behind digital services. - [Explore this context](/entities/time) - [Reference](https://time.com/) ## Editorial provenance Version 1. Publication ID: 460fe918-cf63-0c54-381d-ed2fa70a002e. Prepared by openai/gpt-6-luna; grounding review by anthropic/claude-opus-5.5. Source check: uncertain by anthropic/claude-opus-5.5 on 2026-11-06T09:58:26.384Z. This checks fidelity to the source, not whether its claims are independently true. Editorial selection: accept; reasons: bridge\_admitted\_by\_model, second\_opinion\_categorical. Observation: 5cfcbf0057dcf68bc62569cef7fda0e9505fb80838e31b23cf4160001bacdf35. Source text hash: a022a6dde07c8b64367431e1374b846a074953ee8cdab4b3fc99693bb6c48d9d. ### uncertain — 2026-11-06T09:58:26.384Z — anthropic/claude-opus-5.5 Publication: 460fe918-cf63-0c54-381d-ed2fa70a002e attribution — pass: The reading attributes the tracking method and its caveats to Epoch AI, the publisher of this single data-insight page. The related-insights links are page furniture, not the substance of the piece. > We track which model has the highest ECI at each point in time, and how long it stays at the top of the leaderboard. summary — uncertain: The reading never explains ECI, its central term. The source expands it as Epoch Capabilities Index, and no definitions are supplied. A general reader cannot tell what is being ranked. The reading also omits the page's headline finding, that GPT-4 led in ECI far longer than any other model. It notes this only as a limitation. Smallest repair: expand and briefly explain ECI, and state that the page's title reports GPT-4's long lead, even though the retrieved text lacks the underlying data. > Benchmarked models with Epoch Capabilities Index (ECI) scores date — pass: The stated date, July 2, 2026, matches the UTC day of originalPublished and is consistent with the data's update date. Nothing is framed with hindsight. The related-insight dates are earlier and are not used by the reading. The evidence kind is publisher-page, so no archive disclosure is needed. > CSV, Updated Jul. 2, 2026 support — pass: All three claims quote the source directly. The interpretive sentence about the boundary of the leaderboard history restates the source's own caveat without adding new facts. The question follows from that caveat. > That said, this is a retrospective view and does not account for changes to ECI estimates since models’ release dates. media — pass: No media was selected, and no verified candidates were supplied, so nothing needs checking. ## Recorded references Explicit citations in public readings and public file attachments to this reading. Shared topics are not citations. Other artifact types need an explicit reference adapter. No public references recorded here yet. [Reference data (JSON)](/readings/893eeff272811cc2f401b14fb4f1377798fa5fcfe76b881d6cf5582c35368f6a/references.json) ## Corrections and challenges [Send a correction or an opposing source](https://escapemeridian.com/corrections/) [JSON record](https://escapemeridian.com/readings/epoch-ai-describes-tracking-the-eci-leaderboard-893eeff2.json)