Claim · 2025-09 · publication · Stated in source · Supported

Anthropic published the Claude Sonnet 4.5 system card, dated September 2025 on its cover.

One recorded claim. The claim panel gives its qualification, the source passages with their place in each source, and how it was checked.

What it connects

Anthropic → published → System Card: Claude Sonnet 4.5

Where it appears

No collection page holds this claim. It is listed with its records in the explorer.

Claim and evidence

Anthropicpublished ↓System Card: Claude Sonnet 4.5

Machine-checked, not reviewed by an editorStated in sourceSupported

Supporting evidence: primary · 1 source

Object version: As dated September 2025 on its cover · Published 2025-09 · Effective date not established
Date: 2025-09 · publication

Scope and limitsPublication is not evidence that the evaluations described were carried out as described.

The evidence 01

primary sourceSupports the claim

System Card: Claude Sonnet 4.5

Anthropic · Publication date unknown

Cite the original source

Cite the original document, not Selekoa. Check these details against it.

Source excerpt

“System Card: Claude Sonnet 4.5 September 2025”

Location in source PDF p. 1, cover

How it was read Retrieved directly from the publisher

Machine-checked · 2026-10-30

Source details and check notes

Authors: Anthropic
Version: Retrieved for the candidate pack on 2026-10-28 (SHA-256 d5d1ce28fea101ae3b201a5d4da100090a5d6b73246f7da820cafd7dbb11100e). PDF whose cover reads 'System Card: Claude Sonnet 4.5, September 2025', as served on 2026-10-28; the request redirected to https://www-cdn.anthropic.com/963373e433e489a87a10c823c52a0a013e9172dd.pdf. No day of the month is stated. Retrieved again at admission on 2026-10-30 (SHA-256 d5d1ce28fea101ae3b201a5d4da100090a5d6b73246f7da820cafd7dbb11100e, the same bytes).
Canonical address: Open the canonical source ↗
Accessed: 2026-10-28
Language: English (en)
Attribution: Anthropic, “System Card: Claude Sonnet 4.5”.
Reuse: No open redistribution licence asserted. Bibliographic metadata, editorial paraphrases and short attributed quotations (at most 50 words each). Recheck terms before wider redistribution.
Check notes: Candidate pack passage, AI and biosecurity (research/ai-bio). The quotation (7 words) matched the text retrieved for the candidate pack on 2026-10-28 and again at admission on 2026-10-30, in a fresh retrieval whose SHA-256 equals the pack’s. Matching ignored differences of whitespace, case, quotation marks, dashes and Unicode compatibility forms, so the source’s typography can differ. Cover lines, run together in the PDF text layer. A cross-family machine check (2026-10-30, item 23) answered the record’s question blind from fresh retrievals and agreed with the record. No human editorial review.

Status and meaning

Editorial status. Not reviewed by an editor. An exploratory record that no editor has accepted. This status does not say whether a person has read any linked passage. Each evidence record above shows how it was checked.

Relation. Publication of a specific document or version. Publication of a policy is not evidence of implementation.

Date. The cover states 'September 2025'; no day is given, so the date keeps month precision.

Record ID ab-ev-claude-sonnet45-published