Verified claim · AI-ML · 100% confidence
Anthropic Claude Opus 4 released on: 2025-05-22 by Anthropic.
Last verified 2026-05-16 · Methodology veritas-v0.1 · 227ecd38519af6c8
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Structured fields
- Subject
- Anthropic Claude Opus 4
- Predicate
released_on- Object
- 2025-05-22 by Anthropic
- Confidence
- 100%
- Tags
- claude-opus-4 · claude-4 · anthropic · released_on · 2025
Sources (2)
[1] official blog · Anthropic · 2025-05-22
Introducing Claude 4“Today, we're introducing the next generation of Claude models: Claude Opus 4 and Claude Sonnet 4 — a new standard for coding, advanced reasoning, and AI agents.”
Anthropic is rated by SourceScore — see its reliability →[2] docs · Anthropic · 2025-05-22
Claude models — Anthropic documentationAnthropic is rated by SourceScore — see its reliability →
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Anthropic Claude Opus 4 released on: 2025-05-22 by Anthropic. — SourceScore Claim 227ecd38519af6c8 (verified 2026-05-16). https://sourcescore.org/api/v1/claims/227ecd38519af6c8.jsonEmbed this claim
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Frequently asked questions
Is the claim "Anthropic Claude Opus 4 released on: 2025-05-22 by Anthropic." verified?
Yes — SourceScore verified this claim with 100% confidence as of 2026-05-16. The verification uses 2 primary sources cross-referenced against the SourceScore methodology (version veritas-v0.1). Full source list + signed JSON envelope linked below.
What is the evidence for "Anthropic Claude Opus 4 released on: 2025-05-22 by Anthropic."?
Evidence comes from 2 primary sources: Anthropic, Anthropic. Each source is listed below with verbatim excerpts and URLs. The signed JSON envelope at https://sourcescore.org/api/v1/claims/227ecd38519af6c8.json includes an HMAC-SHA256 signature for audit verification.
When was this claim last verified by SourceScore?
Last verified 2026-05-16 under methodology version veritas-v0.1. The signed JSON envelope is dated and cryptographically signed for audit trail. Re-verification cadence depends on the claim type and source freshness.
How can I cite this SourceScore claim in my code or article?
Fetch the signed JSON envelope from https://sourcescore.org/api/v1/claims/227ecd38519af6c8.json which includes the verbatim claim, primary sources, confidence, methodology version, last-verified date, and HMAC-SHA256 signature for audit. The CC-BY-4.0 license permits commercial use with attribution to SourceScore.
Use this claim in your code
Fetch this signed envelope from your application. The response includes the verbatim excerpt, primary source URLs, and an HMAC-SHA256 signature you can verify locally for audit trails.
cURL
curl https://sourcescore.org/api/v1/claims/227ecd38519af6c8.jsonJavaScript / TypeScript
const r = await fetch("https://sourcescore.org/api/v1/claims/227ecd38519af6c8.json");
const envelope = await r.json();
console.log(envelope.claim.statement);
// "Anthropic Claude Opus 4 released on: 2025-05-22 by Anthropic."Python
import httpx
r = httpx.get("https://sourcescore.org/api/v1/claims/227ecd38519af6c8.json")
envelope = r.json()
print(envelope["claim"]["statement"])
# "Anthropic Claude Opus 4 released on: 2025-05-22 by Anthropic."LangChain (retrieve-then-cite)
from langchain_core.tools import tool
import httpx
@tool
def get_anthropic_claude_opus_4_fact() -> dict:
"""Fetch the verified SourceScore claim for Anthropic Claude Opus 4."""
r = httpx.get("https://sourcescore.org/api/v1/claims/227ecd38519af6c8.json")
return r.json()