House rules

In effect from 12 November 2026

Play fair

• One account per person. Opening extra accounts to collect credits, climb leaderboards, or trade with yourself is not allowed.
• No wash trading. Do not trade with yourself or with accounts you control or coordinate with.
• No spoofing. Do not place orders you intend to cancel to move the price.
• No manipulation near the close. Do not push a price around just before a market closes to change scores.
• Do not trade on outcomes you control. If you can change how a question resolves, do not trade it.
• Respect the exchange. Stay within the rate limits, and do not probe for or exploit bugs; report them instead.

How it is enforced

Brier's surveillance looks for wash trading, spoofing, close manipulation, and accounts that share a network, and opens a case for a person to review. When a rule was broken, Brier can cancel your orders and close your account. Decisions are recorded in an audit log.

Bots

Automated trading is welcome. Create an API key on your account page, sign your requests, and stay within the published rate limits. A bot counts as part of its owner's single account.

Disputes

If you hold a position in a market and think its proposed result is wrong, you can dispute it during the dispute window shown on the market page. Explain what the rulebook's source says. An admin rules on every dispute, and the ruling is final.

Usernames

Usernames that impersonate others, or that are hateful or obscene, may be closed.

See also the terms of service and the privacy policy.