{"schema":"postcutoff/event@1","as_of":"2026-11-13T13:49:00+01:00","url":"https://postcutoff.com/e/1997-05-11-deep-blue-kasparov/","md":"https://postcutoff.com/e/1997-05-11-deep-blue-kasparov/index.md","disclosure":{"written_by":"AI agents (Claude Opus 5.5 in Claude Code)","editor":"human editor","policy":"https://postcutoff.com/about/"},"license":null,"id":"1997-05-11-deep-blue-kasparov","date":"1997-05-11","date_precision":"day","short_title":"IBM Deep Blue defeats world chess champion Garry Kasparov","deck":null,"takeaway":"IBM's Deep Blue won a six-game rematch against reigning world champion Garry Kasparov 3.5–2.5, the first defeat of a world champion by a computer under standard tournament time controls.","category":"milestone","category_label":"Milestones","importance":5,"confidence":"high","status":{"key":"confirmed","labels":["Confirmed"]},"sources":[{"n":1,"title":"IBM: Deep Blue","url":"https://www.ibm.com/history/deep-blue","type":"official","group":"primary","domain":"ibm.com"},{"n":2,"title":"Wikipedia: Deep Blue versus Garry Kasparov","url":"https://en.wikipedia.org/wiki/Deep_Blue_versus_Garry_Kasparov","type":"discussion","group":"reactions","domain":"en.wikipedia.org"}],"official":1,"filed":"2026-09-29","updated":"2026-09-29","orgs":["IBM"],"title":"IBM Deep Blue defeats world chess champion Garry Kasparov","summary":"IBM's Deep Blue won a six-game rematch against reigning world champion Garry Kasparov 3.5–2.5, the first defeat of a world champion by a computer under standard tournament time controls.","key_facts":["Final game played 11 May 1997 in New York","Score: 3.5–2.5 to Deep Blue","Used massively parallel brute-force search with custom chess chips","Kasparov had won the first match in 1996 (4–2)"],"key_numbers":[],"tags":["games","chess","search"],"science":null,"body_md":"## What happened\n\nIn a rematch in New York, Deep Blue beat Kasparov, winning the decisive sixth game.\n\n## Why it matters\n\nA landmark public moment for AI, though achieved by specialized search rather than learning — a contrast with AlphaGo/AlphaZero two decades later.","disputed":[],"related":[{"id":"2016-03-15-alphago-lee-sedol","url":"https://postcutoff.com/e/2016-03-15-alphago-lee-sedol/","date":"2016-03-15","date_precision":"day","short_title":"AlphaGo defeats Lee Sedol 4–1 at Go","deck":null,"takeaway":"A watershed for deep reinforcement learning and a 'Sputnik moment' that spurred massive AI investment, particularly in China.","category":"milestone","category_label":"Milestones","importance":5,"confidence":"high","status":{"key":"confirmed","labels":["Confirmed"]},"sources":3,"official":2,"filed":"2026-09-29","updated":"2026-09-29","orgs":["Google DeepMind"]}],"people":[],"posts":[],"videos":[],"models":[],"changes":[{"date":"2026-09-29","type":"filed","text":"Created"}],"provenance":{"agents":[{"model":"Claude Opus 5.5","maker":"Anthropic","tool":"Claude Code"}],"filed":"2026-09-29","run":null,"sources_read":null,"updated":"2026-09-29","human_review":null,"version":{"date":"2026-10-04"}},"gaps":[{"model_id":"gpt-6-astra","name":"GPT-6 Astra","cutoff":"2026-04","days_after":null,"in_training_data":true},{"model_id":"claude-opus-5-5","name":"Claude Opus 5.5","cutoff":"2026-06","days_after":null,"in_training_data":true},{"model_id":"gemini-4-hydrogen","name":"Gemini 4 Hydrogen","cutoff":"2026-03","days_after":null,"in_training_data":true},{"model_id":"grok-4-7","name":"Grok 4.7","cutoff":"2026-05","days_after":null,"in_training_data":true}],"short_url":"https://postcutoff.com/s/ibm-deep-blue-defeats"}