{"bundle_type":"pith_open_graph_bundle","bundle_version":"1.0","pith_number":"pith:2026:2RHNX5NZFBUGNDGKY7QFJVVK6X","short_pith_number":"pith:2RHNX5NZ","canonical_record":{"source":{"id":"2607.20596","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.LG","submitted_at":"2026-07-22T17:33:16Z","cross_cats_sorted":["cs.CL"],"title_canon_sha256":"0fc8d29891b58de889ee6ecae8113f5520d955e9ca78011656810fc5629e804a","abstract_canon_sha256":"ec7025d96d255f58d0dc136b9eb896ae2f4afb92e871a29d6d9921cff51cdb17"},"schema_version":"1.0"},"canonical_sha256":"d44edbf5b92868668ccac7e054d6aaf5e4acc6c11a2d5272569a63cecb989ceb","source":{"kind":"arxiv","id":"2607.20596","version":1},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2607.20596","created_at":"2026-07-24T00:23:24Z"},{"alias_kind":"arxiv_version","alias_value":"2607.20596v1","created_at":"2026-07-24T00:23:24Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2607.20596","created_at":"2026-07-24T00:23:24Z"},{"alias_kind":"pith_short_12","alias_value":"2RHNX5NZFBUG","created_at":"2026-07-24T00:23:24Z"},{"alias_kind":"pith_short_16","alias_value":"2RHNX5NZFBUGNDGK","created_at":"2026-07-24T00:23:24Z"},{"alias_kind":"pith_short_8","alias_value":"2RHNX5NZ","created_at":"2026-07-24T00:23:24Z"}],"events":[{"event_type":"record_created","subject_pith_number":"pith:2026:2RHNX5NZFBUGNDGKY7QFJVVK6X","target":"record","payload":{"canonical_record":{"source":{"id":"2607.20596","kind":"arxiv","version":1},"metadata":{"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.LG","submitted_at":"2026-07-22T17:33:16Z","cross_cats_sorted":["cs.CL"],"title_canon_sha256":"0fc8d29891b58de889ee6ecae8113f5520d955e9ca78011656810fc5629e804a","abstract_canon_sha256":"ec7025d96d255f58d0dc136b9eb896ae2f4afb92e871a29d6d9921cff51cdb17"},"schema_version":"1.0"},"canonical_sha256":"d44edbf5b92868668ccac7e054d6aaf5e4acc6c11a2d5272569a63cecb989ceb","receipt":{"kind":"pith_receipt","key_id":"pith-v1-2026-05","algorithm":"ed25519","signed_at":"2026-07-24T00:23:24.538123Z","signature_b64":"OL25iOZlsjUdanLqE7yVIWGlcnDmy0XI304/XI5KGwoKaY1w/VvpSCI7ClWhSK4AwoGC9BUi4soWBw5chnrOAA==","signed_message":"canonical_sha256_bytes","builder_version":"pith-number-builder-2026-05-17-v1","receipt_version":"0.3","canonical_sha256":"d44edbf5b92868668ccac7e054d6aaf5e4acc6c11a2d5272569a63cecb989ceb","last_reissued_at":"2026-07-24T00:23:24.537171Z","signature_status":"signed_v1","first_computed_at":"2026-07-24T00:23:24.537171Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"source_kind":"arxiv","source_id":"2607.20596","source_version":1,"attestation_state":"computed"},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-07-24T00:23:24Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"jlp393yK2x+Gl0nzsQClfkgeenIGAJe2VU5pri1TF8ypnrfSQWr107PlDI6CmUlHck8EjKcZhiz782fZaI3EDw==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-04T06:09:17.266658Z"},"content_sha256":"64c1e1680765c5e6623efaafd565e28f7e8a78ddd66cf7fe34a39831ea8b300a","schema_version":"1.0","event_id":"sha256:64c1e1680765c5e6623efaafd565e28f7e8a78ddd66cf7fe34a39831ea8b300a"},{"event_type":"graph_snapshot","subject_pith_number":"pith:2026:2RHNX5NZFBUGNDGKY7QFJVVK6X","target":"graph","payload":{"graph_snapshot":{"paper":{"title":"Are Single-Token Sparse Autoencoder Features Causally Necessary? Layer-Depth and SAE-Family Effects","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":["cs.CL"],"primary_cat":"cs.LG","authors_text":"Adriano Koshiyama, Ilham Wicaksono, Kleyton da Costa, Rishi Kalra, Seonglae Cho, Zekun Wu","submitted_at":"2026-07-22T17:33:16Z","abstract_excerpt":"Sparse autoencoder (SAE) features are used to interpret and steer large language models, yet whether a feature's causal role is stable across SAE families remains untested. Single-token features that activate on one vocabulary item provide the diagnostic case where ground truth permits direct comparison. We analyze 3.9M features across six models and three SAE families using zero-ablation at full layer depth. Single-token features cluster 4.7x tighter in decoder space and concentrate in early layers (Layer 0 in GPT2-Small; L0-L4 in Gemma). Ablating them yields Benjamini-Hochberg-significant lo"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2607.20596","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2607.20596/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"},"verdict_id":null},"signer":{"signer_id":"pith.science","signer_type":"pith_registry","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54"},"created_at":"2026-07-24T00:23:24Z","supersedes":[],"prev_event":null,"signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"62nqEcJ7kZZVaPvjOdtDW73AKJTUA5w1TJ+X9NTFXQj4R3MtlBPMDEHN6gEYIFyQivQgNfXhogILyF17rxTsAQ==","signed_message":"open_graph_event_sha256_bytes","signed_at":"2026-08-04T06:09:17.267177Z"},"content_sha256":"cb9a46e72521eb4878d9a4ccf0a80e9f20c49226e304d5ec86e8677c4b37f5c8","schema_version":"1.0","event_id":"sha256:cb9a46e72521eb4878d9a4ccf0a80e9f20c49226e304d5ec86e8677c4b37f5c8"}],"timestamp_proofs":[],"mirror_hints":[{"mirror_type":"https","name":"Pith Resolver","base_url":"https://pith.science","bundle_url":"https://pith.science/pith/2RHNX5NZFBUGNDGKY7QFJVVK6X/bundle.json","state_url":"https://pith.science/pith/2RHNX5NZFBUGNDGKY7QFJVVK6X/state.json","well_known_bundle_url":"https://pith.science/.well-known/pith/2RHNX5NZFBUGNDGKY7QFJVVK6X/bundle.json","status":"primary"}],"public_keys":[{"key_id":"pith-v1-2026-05","algorithm":"ed25519","format":"raw","public_key_b64":"stVStoiQhXFxp4s2pdzPNoqVNBMojDU/fJ2db5S3CbM=","public_key_hex":"b2d552b68890857171a78b36a5dccf368a953413288c353f7c9d9d6f94b709b3","fingerprint_sha256_b32_first128bits":"RVFV5Z2OI2J3ZUO7ERDEBCYNKS","fingerprint_sha256_hex":"8d4b5ee74e4693bcd1df2446408b0d54","rotates_at":null,"url":"https://pith.science/pith-signing-key.json","notes":"Pith uses this Ed25519 key to sign canonical record SHA-256 digests. Verify with: ed25519_verify(public_key, message=canonical_sha256_bytes, signature=base64decode(signature_b64))."}],"merge_version":"pith-open-graph-merge-v1","built_at":"2026-08-04T06:09:17Z","links":{"resolver":"https://pith.science/pith/2RHNX5NZFBUGNDGKY7QFJVVK6X","bundle":"https://pith.science/pith/2RHNX5NZFBUGNDGKY7QFJVVK6X/bundle.json","state":"https://pith.science/pith/2RHNX5NZFBUGNDGKY7QFJVVK6X/state.json","well_known_bundle":"https://pith.science/.well-known/pith/2RHNX5NZFBUGNDGKY7QFJVVK6X/bundle.json"},"state":{"state_type":"pith_open_graph_state","state_version":"1.0","pith_number":"pith:2026:2RHNX5NZFBUGNDGKY7QFJVVK6X","merge_version":"pith-open-graph-merge-v1","event_count":2,"valid_event_count":2,"invalid_event_count":0,"equivocation_count":0,"current":{"canonical_record":{"metadata":{"abstract_canon_sha256":"ec7025d96d255f58d0dc136b9eb896ae2f4afb92e871a29d6d9921cff51cdb17","cross_cats_sorted":["cs.CL"],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.LG","submitted_at":"2026-07-22T17:33:16Z","title_canon_sha256":"0fc8d29891b58de889ee6ecae8113f5520d955e9ca78011656810fc5629e804a"},"schema_version":"1.0","source":{"id":"2607.20596","kind":"arxiv","version":1}},"source_aliases":[{"alias_kind":"arxiv","alias_value":"2607.20596","created_at":"2026-07-24T00:23:24Z"},{"alias_kind":"arxiv_version","alias_value":"2607.20596v1","created_at":"2026-07-24T00:23:24Z"},{"alias_kind":"doi","alias_value":"10.48550/arxiv.2607.20596","created_at":"2026-07-24T00:23:24Z"},{"alias_kind":"pith_short_12","alias_value":"2RHNX5NZFBUG","created_at":"2026-07-24T00:23:24Z"},{"alias_kind":"pith_short_16","alias_value":"2RHNX5NZFBUGNDGK","created_at":"2026-07-24T00:23:24Z"},{"alias_kind":"pith_short_8","alias_value":"2RHNX5NZ","created_at":"2026-07-24T00:23:24Z"}],"graph_snapshots":[{"event_id":"sha256:cb9a46e72521eb4878d9a4ccf0a80e9f20c49226e304d5ec86e8677c4b37f5c8","target":"graph","created_at":"2026-07-24T00:23:24Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"graph_snapshot":{"author_claims":{"count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","strong_count":0},"builder_version":"pith-number-builder-2026-05-17-v1","claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"integrity":{"available":true,"clean":true,"detectors_run":[],"endpoint":"/pith/2607.20596/integrity.json","findings":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938","summary":{"advisory":0,"by_detector":{},"critical":0,"informational":0}},"paper":{"abstract_excerpt":"Sparse autoencoder (SAE) features are used to interpret and steer large language models, yet whether a feature's causal role is stable across SAE families remains untested. Single-token features that activate on one vocabulary item provide the diagnostic case where ground truth permits direct comparison. We analyze 3.9M features across six models and three SAE families using zero-ablation at full layer depth. Single-token features cluster 4.7x tighter in decoder space and concentrate in early layers (Layer 0 in GPT2-Small; L0-L4 in Gemma). Ablating them yields Benjamini-Hochberg-significant lo","authors_text":"Adriano Koshiyama, Ilham Wicaksono, Kleyton da Costa, Rishi Kalra, Seonglae Cho, Zekun Wu","cross_cats":["cs.CL"],"headline":"","license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.LG","submitted_at":"2026-07-22T17:33:16Z","title":"Are Single-Token Sparse Autoencoder Features Causally Necessary? Layer-Depth and SAE-Family Effects"},"references":{"count":0,"internal_anchors":0,"resolved_work":0,"sample":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2607.20596","kind":"arxiv","version":1},"verdict":{"created_at":null,"id":null,"model_set":{},"one_line_summary":"","pipeline_version":null,"pith_extraction_headline":"","strongest_claim":"","weakest_assumption":""}},"verdict_id":null}}],"author_attestations":[],"timestamp_anchors":[],"storage_attestations":[],"citation_signatures":[],"replication_records":[],"corrections":[],"mirror_hints":[],"record_created":{"event_id":"sha256:64c1e1680765c5e6623efaafd565e28f7e8a78ddd66cf7fe34a39831ea8b300a","target":"record","created_at":"2026-07-24T00:23:24Z","signer":{"key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signer_id":"pith.science","signer_type":"pith_registry"},"payload":{"attestation_state":"computed","canonical_record":{"metadata":{"abstract_canon_sha256":"ec7025d96d255f58d0dc136b9eb896ae2f4afb92e871a29d6d9921cff51cdb17","cross_cats_sorted":["cs.CL"],"license":"http://creativecommons.org/licenses/by/4.0/","primary_cat":"cs.LG","submitted_at":"2026-07-22T17:33:16Z","title_canon_sha256":"0fc8d29891b58de889ee6ecae8113f5520d955e9ca78011656810fc5629e804a"},"schema_version":"1.0","source":{"id":"2607.20596","kind":"arxiv","version":1}},"canonical_sha256":"d44edbf5b92868668ccac7e054d6aaf5e4acc6c11a2d5272569a63cecb989ceb","receipt":{"algorithm":"ed25519","builder_version":"pith-number-builder-2026-05-17-v1","canonical_sha256":"d44edbf5b92868668ccac7e054d6aaf5e4acc6c11a2d5272569a63cecb989ceb","first_computed_at":"2026-07-24T00:23:24.537171Z","key_id":"pith-v1-2026-05","kind":"pith_receipt","last_reissued_at":"2026-07-24T00:23:24.537171Z","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","receipt_version":"0.3","signature_b64":"OL25iOZlsjUdanLqE7yVIWGlcnDmy0XI304/XI5KGwoKaY1w/VvpSCI7ClWhSK4AwoGC9BUi4soWBw5chnrOAA==","signature_status":"signed_v1","signed_at":"2026-07-24T00:23:24.538123Z","signed_message":"canonical_sha256_bytes"},"source_id":"2607.20596","source_kind":"arxiv","source_version":1}}},"equivocations":[],"invalid_events":[],"applied_event_ids":["sha256:64c1e1680765c5e6623efaafd565e28f7e8a78ddd66cf7fe34a39831ea8b300a","sha256:cb9a46e72521eb4878d9a4ccf0a80e9f20c49226e304d5ec86e8677c4b37f5c8"],"state_sha256":"dac982f7d8754e8e83b888261ba1732546d53559dac93671c5dfbebd5ef0984e"},"bundle_signature":{"signature_status":"signed_v1","algorithm":"ed25519","key_id":"pith-v1-2026-05","public_key_fingerprint":"8d4b5ee74e4693bcd1df2446408b0d54","signature_b64":"7hWQDH5jzQVGjU8Qgu0HClAVKHJwiZjDjQRk1kuMVc5A1f0E6d1EeCgvPYb2CLDoBAn4GD/a9/jkwYZw4bJfBw==","signed_message":"bundle_sha256_bytes","signed_at":"2026-08-04T06:09:17.271927Z","bundle_sha256":"c5d58171fe242f1fe960cf06777423d88e8a1994869dd78e944291471e9cd91c"}}