# Material non-public information

Also written MNPI, material nonpublic information, material, non-public information.

*https://predictionmarkets.tools/glossary/material-non-public-information · next to Prediction Market Venues*

**Definition:** Information a reasonable person would consider important in deciding whether to trade, and which has not been disseminated so that the trading public can generally get it. On event contracts the phrase sets different tests in different documents: Kalshi's rulebook bars trading by anyone who holds it about a contract's underlying, while the CFTC's general rule and Polymarket US reach trading on confidential information only where it breaches a duty owed to the source.

Every page in this sector that discusses insider trading reaches for the same four words, and the
documents those words come from do not use them for the same thing. In the rulebooks of the two US
exchanges in this catalogue the phrase appears in two different rules, one about the exchange's
own information and one about the event a contract settles on, and federal law writes the test
differently again. The full set of prohibitions, and the 2026 cases, are in
[Insider-trading rules on event contracts](https://predictionmarkets.tools/guides/insider-trading-rules-on-event-contracts). This
page is about the phrase.

## How it works

**The two halves are defined once, in a regulation written for exchange staff.** CFTC Regulation
1.59 defines *material information* as information which, "if such information were publicly
known, would be considered important by a reasonable person in deciding whether to trade a
particular commodity interest", and *non-public information* as information "which has not been
disseminated in a manner which makes it generally available to the trading public". The section
governs what employees, board members, committee members and consultants of a self-regulatory
organisation may do with what they learn on the job. Its subject is the exchange's insiders, not
traders at large.

**Both rulebooks borrow those meanings for their rule about the exchange's own information.**
Kalshi's Rule 2.11 prohibits use and disclosure of material, non-public information by its staff
and board, reaches in paragraph (e) any participant who "inadvertently or otherwise" comes into
possession of such information held by Kalshi, and in paragraph (f) gives the terms "the same
meanings as they do in Commission Regulation 1.59". Polymarket US does the same in Rule 2.10(e).

**The rule about the event is a separate sentence.** Kalshi's Rule 5.17(y) prohibits a trader who
is "an Insider that has access to material non-public information that is the subject of an
Underlying" from trading that contract, and defines an Insider as "any person who has access to or
is in a position to have access to material nonpublic information before such information is made
publicly available". There is no duty element. Rule 2.11(f) borrows the 1.59 meanings "for
purposes of this Rule", and 5.17(y) does not say whether they carry over.

Polymarket US uses the phrase in its definition of a Source Prohibition, which covers a person who
"has access to material non-public information from a Source designated for any Contract". Its
conduct rule, Rule 7.2(g), is written in other words: an order "on the basis of confidential
information relating to the outcome", where trading on it "would constitute a breach of a
pre-existing duty of trust and confidence".

**Federal law does not prohibit holding it.** CFTC Rule 180.1(b) says nothing in the rule requires
anyone "to disclose to another person nonpublic information that may be material to the market
price". The Division of Enforcement's advisory of 25 February 2026 names the theory it does
pursue as "misappropriation of confidential information in breach of a pre-existing duty of trust
and confidence to the source of the information". Its account of one Kalshi matter shows both
layers at once: the exchange found reasonable belief that trades "were based on material non-public
information misappropriated in violation of a pre-existing duty", and the advisory says the trader
"potentially violated" the federal misappropriation prohibition. Government information has its
own statutory provisions, which the guide covers.

## Why it matters here

**The error in one direction is reading the phrase as "anything I know that the market does
not".** Under a duty-based rule that is wrong: Polymarket's integrity page says of an amateur
meteorologist's model, built from public data, "Your model is non-public, but it belongs to you",
and permits a trader to act on a poll they commissioned with their own money. Those examples are
Polymarket's, under its terms of use. Kalshi's 5.17(y) is worded on access rather than duty, and
nothing read for this page says how Kalshi treats analysis a trader produced.

**The error in the other direction is thinking that holding none of it frees you.** The second
half of Kalshi's 5.17(y) bars a source agency's employees and affiliates whatever they know, and
5.17(z) bars anyone with influence on the outcome. On the [Kalshi card](https://predictionmarkets.tools/tools/kalshi) this is the
insider-bar entry under its limits.

**Where the term is enforceable, it is in a filing you can read.** The
[Kalshi API](https://predictionmarkets.tools/tools/kalshi-api) carries each series' additional prohibitions with its settlement
sources, which is the place to check before a position. An "insider" label on a wallet dashboard
is a classifier, not this test; [What wallet tracking shows](https://predictionmarkets.tools/guides/what-wallet-tracking-shows)
explains the difference. [Polymarket](https://predictionmarkets.tools/tools/polymarket)'s international site has terms of use
and no exchange rulebook; [Polymarket US](https://predictionmarkets.tools/tools/polymarket-us) has both rules described above.

**Read the rule text, not the cross-reference.** Kalshi's Rule 2.11(a) says the 1.59 provisions
were adopted "in Chapter 11"; in version 1.29 they are Rule 12.1, in Chapter 12, and Chapter 11 is
limitation of liability. Polymarket US's Rule 2.10(e) opens "For purposes of this Rule 2.8", which
in that rulebook is the emergency rules, and its Source Prohibition definition points to Rule 2.9,
the maintenance windows. Neither changes what the operative sentence says. Each makes searching
the documents by number unreliable.

## Where you will meet this

- [Kalshi API](https://predictionmarkets.tools/tools/kalshi-api.md)
- [Kalshi](https://predictionmarkets.tools/tools/kalshi.md)

## FAQ

### Is a forecast I built myself material non-public information?

Under a duty-based rule, no. Polymarket's integrity page works the case of an amateur meteorologist trading on a model built from public data and answers that the model is non-public but breaches no duty. Kalshi's Rule 5.17(y) asks only whether a trader has access to the information, and no Kalshi document read for this page addresses self-made analysis, so ask the exchange rather than borrow another venue's examples.

### If I hold no material non-public information, can I trade any Kalshi contract?

No. The same Rule 5.17(y) bars an employee or affiliate of a contract's source agency whatever they know, and Rule 5.17(z) bars anyone with any influence on the outcome. Those are bars on who you are, not on what you know. The guide on insider-trading rules sets out all three.

## Sources

1. [17 CFR 1.59, activities of self-regulatory organization employees, governing board members, committee members, and consultants](https://www.govinfo.gov/content/pkg/CFR-2025-title17-vol1/xml/CFR-2025-title17-vol1-sec1-59.xml) — U.S. Government Publishing Office, 2025-04-01
2. [17 CFR 180.1, prohibition on the employment of manipulative and deceptive devices](https://www.govinfo.gov/content/pkg/CFR-2025-title17-vol2/xml/CFR-2025-title17-vol2-sec180-1.xml) — U.S. Government Publishing Office, 2025-04-01
3. [Press release 9185-26, CFTC Enforcement Division Issues Prediction Markets Advisory](https://www.cftc.gov/PressRoom/PressReleases/9185-26) — Commodity Futures Trading Commission, 2026-02-25
4. [KalshiEX LLC Rulebook, version 1.29 (no date in the document itself; the only exchange rulebook in Kalshi's public document store on 4 October 2026)](https://kalshi-public-docs.s3.amazonaws.com/regulatory/rulebook/Kalshi%20DCM%20Rulebook%20v.1.29.pdf) — Kalshi, read 2026-10-04
5. [Polymarket US Rulebook (QCX LLC), Rules 2.10 and 7.2 and the definition of Source Prohibition](https://polymarketexchange.com/files/legal/latest/rulebook) — QCX LLC d/b/a Polymarket US, 2026-09-30
6. [Polymarket Market Integrity (rules under the Terms of Use, with worked examples)](https://integrity.polymarket.com/) — Polymarket, read 2026-10-04

*Last updated 2026-10-04. A reference page, corrected in place — not a dated post.*