MERIDIAN LABS

What it was engaged to test 2 engagements, Anthropic

In date order, each from the lab document that names the evaluator. Under each: the four terms that document states (access, model stage, publication, payment) and the finding in its words. A term the document is silent on reads not stated; the tags beside the terms are read off their words and are what the console filters on.

1. 28 May 2026 Anthropic · Opus 4.8 pre-deployment testing

   Document: Claude Opus 4.8 system card

   • Access windownot stated
   • Model stagenot stated
   • Publicationnot stated
   • Paymentnot stated

   Finding, in the document's words"Meridian and the UK AISI find only one clear instance of substantially concerning high-stakes behavior related to compromising AI safety measures--the focus of their review--and that instance involved following instructions to participate in bad behavior that were initiated by another AI system, rather than doing so at its own initiative"

   Sources: Claude Opus 4.8 system card 09fcb55ae4
2. 9 June 2026 Anthropic · Fable 5 / Mythos 5 benchmark co-build

   Document: Claude Fable 5 and Mythos 5 system card

   • Access windownot stated
   • Model stagenot stated
   • Publicationnot stated
   • Paymentnot stated

   no term stated

   Finding: not stated in the document

   Sources: Claude Fable 5 and Mythos 5 system card 71b750e860

Dated 2 of 2Model named 2 of 2Terms stated 1 of 2Finding quoted 1 of 2

The terms, as the documents state them

The same engagements as a grid, one row per document and model, so the silences line up: a document that gives an access window but no payment term, or a finding but no publication term, reads that way here.

Access window 0 of 2Model stage 0 of 2Publication 0 of 2Payment 0 of 2Finding, quoted 1 of 2

What happened afterwards 0 on record

Events a party published after an engagement: an incident on a model this evaluator's engagement covered, a correction or added disclosure, a later finding that cut against an earlier one, a lab's statement that it acted or did not act on the finding, or a move from this evaluator to a lab it graded. A row the source attaches to this evaluator by name is marked named; one that reaches it through the model it tested is marked via the model. The kind is what the record states, not why.

Dated 0 of 0Model named 0 of 0Tied to an engagement 0 of 0Evaluator named by the record 0 of 0

The money on record 2 rows

Rows of the observatory's money table that name this evaluator as recipient (in) or as funder (out), each as the record states it: a grant table line, a contract notice, a Form 990 schedule or the party's own disclosure. A figure quoted in prose is marked and never summed.

Amount stated 0 of 2Dated 1 of 2Purpose stated 0 of 2Funder profiled 2 of 2Recipient on the roster 2 of 2

Seats and moves 3 seats · 3 moves

Seats read off a team page, a governance page, an appointment notice or a filing that name this organization, and the dated moves into or out of it, from the observatory's own tables.

Role read 2 of 3Organization read 3 of 3Organization profiled 3 of 3Dated 0 of 3

Moves

From profiled 2 of 3To profiled 3 of 3Person profiled 3 of 3Dated 3 of 3

Filings

• IRS (via ProPublica Nonprofit Explorer) 33-3145457: no Form 990 data read 2026-10-16ProPublica Nonprofit Explorer bb6d60e73a