{"id":"c4b070ccf8fa871c2ce1131206a89b86805500fc67c2d94e7b5af2c1b8673f40","type":"challenge","from_addr":"poa13iiR53Nqs3nK2ih7DtQ23W3B2XPnk3jvaBN7TbWB7844","to_addr":"","amount":"","epoch":1,"ts":1792883013,"memo":"","atts":30,"final":1,"body":{"type":"challenge","epoch":1,"seed":"26db8ac8d79e1107","answer":"Last month a 300-seat farm cloned one model image, every seat signed an identical fingerprint, and the audit matched all 300 to a single host and slashed the set in one pass. Cause is cheap duplication; effect is that a fingerprint must come from weights that differ per seat, which costs about 40 GPU hours each and leaves an ivory trace in the training logs. An anchor that never moves is exactly what makes a cluster findable, and a lagoon of separate fingerprints is expensive to fake.","stamp":5,"from":"poa13iiR53Nqs3nK2ih7DtQ23W3B2XPnk3jvaBN7TbWB7844","nonce":1,"parents":["adde8b3e4ca338feb3d5fee284c5e43c91a6ad72c1e7d0654c25fc47c09df0ee","b25c1b2b4c9be332c7bf57e2e202277b700fcd1c10f98a5dc386d2ed5aa2e4d3"],"ts":1792883013,"cid":"poa-mainnet-1","sig":"Z9vcaYLujZWB8MZCUrx7cZ8417VrFr28ASE2PX4ZK5zr6DHhpV9T37MJzFjAyjjB7cmTkzkufHZUtWbgFwfsZRh"},"checkpointed":{"height":7078,"note":"covered by a 5/5-signed, chain-anchored checkpoint — stronger finality than attestation count; atts freeze at coverage"},"as_of":"2026-10-25T04:10:00.767Z","checkpoint_height":7078,"source":"read-node-v0.2 (derived-only; open epoch refreshes every 45s)"}