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Independent ratings · research · data for event markets

Event markets grew up.
Their infrastructure didn't.

Two research desks independently project ~$1 trillion in annual prediction-market volume by 2030 — and $1.1B+ of volume has already settled in controversy. Brierly is the independent ratings firm for the fine print: 0–100 settlement-risk grades on every liquid Kalshi and Polymarket market, published from a public methodology, backed by the only coded database of how these markets actually fail.

connecting to venues…
Markets graded live
top by volume, both venues
21
Coded disputes
2025–26, every case sourced
$1.1B+
Disputed volume
EMU Index
priced disagreement, live
Data feeds live

The problem is the fine print

and it is detectable in advance
01 — THE FAILURE MODE

Markets settle on language, not reality

A $237M market settled on whether an outfit was a "suit." A $204M market died on a confirmation Iran never gave. Biden met Trudeau on television and "Will Biden meet Trudeau?" still resolved No. 21 coded cases, five repeatable failure types — all in the public dispute database.

02 — THE PRODUCT

RuleScore™: grades on the contract, not the trade

A deterministic 0–100 settlement-risk grade on every liquid market, five failure-type subscores, every flagged phrase quoted from the live rules text, and the SHA-256 of exactly what was graded. The methodology is public — any grade can be reproduced.

03 — WHO NEEDS IT

Everyone pricing these contracts

Market makers quoting 2,000 books. Funds entering through Clear Street and Tradeweb. Exchanges re-papering applications against the June 2026 CFTC proposal. The integrity layer is how an asset class graduates — comp: Covenant Review → Fitch.

Two exchanges. Two APIs. One graded view.

KALSHI

GET /markets/KXFEDDECISION-26JUN-H0

{"ticker": "KXFEDDECISION-26JUN-H0",
 "yes_ask_dollars": "0.9800",
 "volume_24h_fp": "701500.20",
 "rules_primary": "If the upper
  bound of the Federal Funds
  Target Range is..."}

POLYMARKET

GET /markets/0xde04b189b3f1...

{"conditionId": "0xde04b189...",
 "outcomePrices": "[\"0.987\",
   \"0.013\"]",
 "clobTokenIds": "[\"3076781...\"]",
 "volume24hr": 4157473.13}

BRIERLY

one view, both venues —
matched, normalized, fee-netted,
graded for settlement risk.

Fed holds (June): K 98.5¢ · P 99.4¢
Consensus 98.9% · gap inside fees
RuleScore 22 · Low dispute risk
rules sha256: 9f2c…e1 (reproducible)

Live grades right now

All grades →

Proof, not promises

Live right now

The dispute record

21 coded cases, $1.1B+ in reported volume on contested markets, every case sourced. The taxonomy behind the grades is public — and the white paper is headed to SSRN with the full dataset and methodology attached.

Open the database

The scored record

Desk calls are probability-stamped at publication, auto-resolved against the venues, and committed to a versioned git registry — once the repository opens to the public at launch, the no-retro-editing claim is independently auditable in the commit history. First resolution: June 17 (FOMC).

See the ledger

Also from Brierly

the supporting lines

Everything is free during early access.

Grades, dashboards, the index, the tax engine, the research — all of it, free while the record builds in public. Join the list and we'll write when something worth your time ships.