{"updated_at": "2026-10-26T10:12:47Z", "cutoff": "2026-10-26", "report": "https://aiforlawyers.app/report/frontier-models", "pdf": "https://aiforlawyers.app/report/frontier-models.pdf", "title": "Frontier models for legal work", "note": "Counts are public posts, not a survey. Compare bands and the number of voices, not totals. outside_not_our_score holds other publishers' figures, copied with their dates; they are not part of our net or band.", "license": "https://creativecommons.org/licenses/by/4.0/", "attribution": "aiforlawyers.app (AI Vortex), Frontier models for legal work, cutoff Oct 26, 2026, https://aiforlawyers.app/report/frontier-models", "how_to_cite": "https://aiforlawyers.app/method#use", "min_n": 10, "voices": 3473, "our_record": {"families": [{"tool": "Claude", "lab": "Anthropic", "n": 872, "pos": 492, "mixed": 103, "neg": 169, "neutral": 108, "net": 37, "lo": 33, "hi": 41, "confidence": "High"}, {"tool": "ChatGPT", "lab": "OpenAI", "n": 2467, "pos": 832, "mixed": 321, "neg": 1162, "neutral": 152, "net": -13, "lo": -16, "hi": -10, "confidence": "High"}, {"tool": "Gemini", "lab": "Google", "n": 134, "pos": 73, "mixed": 18, "neg": 36, "neutral": 7, "net": 28, "lo": 15, "hi": 39, "confidence": "Medium"}], "by_task": [{"task": "research", "label": "Legal research", "cells": [{"tool": "Claude", "n": 82, "status": "rated", "pos": 49, "neg": 15, "net": 41, "lo": 27, "hi": 54, "confidence": "Medium"}, {"tool": "ChatGPT", "n": 623, "status": "rated", "pos": 148, "neg": 359, "net": -34, "lo": -39, "hi": -28, "confidence": "High"}, {"tool": "Gemini", "n": 31, "status": "rated", "pos": 17, "neg": 4, "net": 42, "lo": 19, "hi": 59, "confidence": "Low"}]}, {"task": "drafting", "label": "Drafting", "cells": [{"tool": "Claude", "n": 141, "status": "rated", "pos": 94, "neg": 14, "net": 57, "lo": 47, "hi": 65, "confidence": "Medium"}, {"tool": "ChatGPT", "n": 573, "status": "rated", "pos": 288, "neg": 160, "net": 22, "lo": 16, "hi": 28, "confidence": "High"}, {"tool": "Gemini", "n": 27, "status": "rated", "pos": 18, "neg": 5, "net": 48, "lo": 20, "hi": 68, "confidence": "Low"}]}, {"task": "summarization", "label": "Summarization", "cells": [{"tool": "Claude", "n": 27, "status": "rated", "pos": 19, "neg": 3, "net": 59, "lo": 33, "hi": 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"hi": -59, "confidence": "Medium"}, {"tool": "Gemini", "n": 9, "status": "few", "pos": 2, "neg": 7, "net": -56, "lo": null, "hi": null, "confidence": null}]}, {"task": "general", "label": "General use", "cells": [{"tool": "Claude", "n": 455, "status": "rated", "pos": 232, "neg": 103, "net": 28, "lo": 22, "hi": 34, "confidence": "High"}, {"tool": "ChatGPT", "n": 790, "status": "rated", "pos": 253, "neg": 394, "net": -18, "lo": -23, "hi": -13, "confidence": "High"}, {"tool": "Gemini", "n": 45, "status": "rated", "pos": 22, "neg": 17, "net": 11, "lo": -11, "hi": 33, "confidence": "Low"}]}], "by_version": [{"family": "Claude", "version": "Claude Opus 4.x", "posts_naming_it": 27, "voices": 15, "status": "rated", "net": 47, "lo": 12, "hi": 70, "latest": "2026-10-06"}, {"family": "Claude", "version": "Claude 3.5 Sonnet", "posts_naming_it": 12, "voices": 10, "status": "rated", "net": 100, "lo": 61, "hi": 99, "latest": "2026-06-07"}, {"family": "Claude", "version": "Claude Opus (unversioned)", 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"rated", "net": 82, "lo": 37, "hi": 95, "latest": "2025-09-13"}, {"family": "ChatGPT", "version": "GPT-3.5", "posts_naming_it": 7, "voices": 7, "status": "few", "net": null, "lo": null, "hi": null, "latest": "2026-06-06"}, {"family": "ChatGPT", "version": "o1", "posts_naming_it": 10, "voices": 7, "status": "few", "net": null, "lo": null, "hi": null, "latest": "2026-02-18"}, {"family": "Gemini", "version": "Gemini 2.x", "posts_naming_it": 29, "voices": 14, "status": "rated", "net": 57, "lo": 22, "hi": 76, "latest": "2026-08-05"}, {"family": "Gemini", "version": "Bard", "posts_naming_it": 27, "voices": 11, "status": "rated", "net": -36, "lo": -69, "hi": 11, "latest": "2025-05-14"}, {"family": "Gemini", "version": "Gemini 3", "posts_naming_it": 22, "voices": 10, "status": "rated", "net": 80, "lo": 41, "hi": 91, "latest": "2026-09-17"}, {"family": "Gemini", "version": "Gemini Advanced / Pro", "posts_naming_it": 12, "voices": 7, "status": "few", "net": null, "lo": null, "hi": null, "latest": "2026-08-24"}], "voices_naming_current_models": [{"model": "Claude Haiku 5.5", "lab": "Anthropic", "released": "2026-10-07", "voices": 0}, {"model": "Claude Sonnet 5.5", "lab": "Anthropic", "released": "2026-09-28", "voices": 0}, {"model": "Claude Opus 5.5", "lab": "Anthropic", "released": "2026-09-22", "voices": 4}, {"model": "Claude Fable 5.1", "lab": "Anthropic", "released": "2026-09-01", "voices": 2}, {"model": "Claude Opus 5", "lab": "Anthropic", "released": "2026-07-24", "voices": 10}, {"model": "Claude Sonnet 5", "lab": "Anthropic", "released": "2026-06-30", "voices": 2}, {"model": "Claude Fable 5", "lab": "Anthropic", "released": "2026-06-09", "voices": 10}, {"model": "GPT-6.1 Sol", "lab": "OpenAI", "released": "2026-09-29", "voices": 0}, {"model": "GPT-6 Sol", "lab": "OpenAI", "released": "2026-09-22", "voices": 0}, {"model": "GPT-6 Luna", "lab": "OpenAI", "released": "2026-09-22", "voices": 0}, {"model": "GPT-6 Astra", "lab": "OpenAI", "released": "2026-09-03", "voices": 2}, {"model": "GPT-5.6 Sol", "lab": "OpenAI", "released": "2026-07-09", "voices": 5}, {"model": "Gemini 4 Argon", "lab": "Google", "released": "2026-10-13", "voices": 0}, {"model": "Gemini 3.8 Flash", "lab": "Google", "released": "2026-09-02", "voices": 0}, {"model": "Gemini 3.1 Pro", "lab": "Google", "released": "2026-02-19", "voices": 4}]}, "outside_not_our_score": {"read": "2026-10-23", "boards": [{"key": "vals_lrb", "name": "Vals Legal Research Bench (All-Pass accuracy)", "url": "https://www.vals.ai/benchmarks/legal_research", "updated": "2026-10-22", "read": "2026-10-23", "metric": "accuracy %"}, {"key": "vals_legalbench", "name": "Vals LegalBench", "url": "https://www.vals.ai/benchmarks/legal_bench", "updated": "2026-10-13", "read": "2026-10-23", "metric": "accuracy %"}, {"key": "aa_index", "name": "Artificial Analysis Intelligence Index v4.3.2", "url": "https://artificialanalysis.ai/leaderboards/models", "updated": null, "read": "2026-10-23", "metric": "index value 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