Terms of Use

By using Crossbook you agree to these terms. If you do not agree, do not use it. Crossbook (pending company formation) may update these terms; the date at the top of this page is when the current version took effect.

Crossbook is an information and analytics site. It reads publicly available prices from third-party prediction market venues, attempts to identify where two venues are quoting the same question, and publishes its own probability estimates scored against those prices over time.

It does not execute, route, place, clear or facilitate any trade. It holds no customer funds and takes no position. It is not a broker, an exchange, a clearing agency, a futures commission merchant, or an investment adviser, and nothing on it should be read as a solicitation to trade anything.

Nothing on Crossbook is investment, trading, legal, tax or financial advice. The probability estimates it publishes are its own opinions, produced in part by automated systems, and are offered as a public record to be judged on their accuracy — not as recommendations to act.

Crossbook is provided as is, with no warranty of accuracy, completeness or timeliness. Specific things you should assume will happen rather than treat as edge cases:

• ·Cross-venue matching is automated and gets things wrong. Two contracts can look like the same question and settle on different terms. See the methodology for the specific ways this fails.
• ·A displayed difference between venues may not be real. It can be an artifact of a wrong match, a stale quote, or a book with nothing behind it.
• ·Prices are delayed. They are refreshed periodically, not streamed, and a venue outage can leave a figure on screen that is hours or days old.
• ·Venues change, reword, suspend and settle their own markets without notice, and Crossbook may reflect that late or not at all.

Trading prediction markets can lose you money. Every decision you make is yours alone, and you are solely responsible for verifying anything here against the venue itself before acting on it. Crossbook links to the underlying market on every page precisely so that you can.

To the fullest extent the law allows, Crossbook (pending company formation) is not liable for any indirect, incidental, consequential, special or punitive damages, or for any lost profits, lost trading opportunity or trading losses, arising from your use of Crossbook.

Total liability for any claim is capped at the greater of the amount you paid Crossbook (pending company formation) in the twelve months before the claim, or zero dollars. Crossbook is free to use, so in practice that cap is zero.

You must be at least 18 to use Crossbook. Whether the venues it describes are lawfully available to you where you live is your responsibility to determine, not Crossbook's. Describing a market is not an assertion that you may legally trade it.

Crossbook has no user accounts and accepts no user submissions. Every forecast in the record is written by the operator, timestamped when it is made, and thereafter immutable — the timestamp and the recorded probability are what make the score meaningful, so they are never edited after the fact.

Resolutions are appended as a log rather than overwritten, so a correction is visible as a correction. The published rules state what qualifies for the record and how it is scored, and they change only by a dated, versioned edit.

Read the site, link to it, quote it. Do not scrape it in bulk, redistribute or resell the data, or run automated access against it. The underlying market data belongs to the venues and their terms govern it; Crossbook's arrangement, matching and estimates are its own.

Kalshi and Polymarket are independent companies with no relationship to Crossbook. Their marks are used nominatively, to say whose market a price came from. Crossbook does not control their data, their uptime, their settlement decisions or their terms, and links to them are not endorsements.

The privacy policy lists every third-party service Crossbook itself relies on.

Crossbook (pending company formation) may suspend or withdraw Crossbook, in whole or in part, at any time and without notice. These terms survive that.

These terms may change. Material changes will move the date at the top of this page. Continuing to use Crossbook after that is acceptance of the revised terms.

These terms are governed by the laws of the operator's home state, without regard to conflict-of-law rules, and any dispute is subject to the exclusive jurisdiction of its courts.

Questions about these terms: crossbookdetroit@gmail.com.