When a prediction market resolution source changed, do not rely on a screenshot of one sentence or assume that every clarification is a new rule. Preserve the original contract, compare the current wording and notice, identify the authority for the change, and use the venue's formal dispute process if the source change could alter the outcome.

Key Takeaways

The contract's full resolution rules—not its short title—identify the controlling source and edge cases.

A correction, fallback, unavailable source, and material source substitution are different events.

Preserve original and current versions with URLs, timestamps, and official notices before arguing about intent.

Test whether the change was authorized, disclosed, consistently applied, and outcome-relevant.

Use the formal review or dispute channel; social posts and edited screenshots are weak evidence.

Prediction market resolution source changed, or only the display?

Start by separating four possibilities. The platform may have fixed a typo without changing the evidence. It may have published a clarification about how an existing source field is read. It may have invoked a fallback already named in the original rule because the primary source became unavailable. Or it may have substituted a different authority or dataset that was not contemplated before trading closed.

Those cases have different consequences. Kalshi explains that each market has its own rules and that the rules summary identifies the outcome criteria and verification source.［1］ Polymarket similarly says that a market's predefined rules specify the resolution source, end date, and edge cases, while the title alone does not control resolution.［3］ These are platform-specific implementations, but both demonstrate why the complete rule matters.

Compare the full text, not only the source name. A webpage redesign, redirect, agency rename, data-series code correction, or revised publication URL may still point to the same authority and measurement. Conversely, a sentence can remain visually similar while the geographic scope, reporting period, threshold, revision policy, or responsible institution changes.

What evidence should you capture first?

Preserve evidence before refreshing every tab or contacting support. Create a small version packet containing:

The market and contract identifier, URL, title, and outcome choices.
The original resolution rules and rules summary, preferably as an export or full-page capture.
The current rules with the capture time and time zone.
The original and current source URLs, publication names, data fields, and release times.
Any official amendment, clarification, market notice, status event, or onchain message.
Your fills and position only to establish standing and timing—not to argue that loss proves error.
The venue's dispute deadline, evidence format, and case number after submission.

Comparison field	Original version	Current version	Why it matters
Source authority	Named agency or publisher	Same or different body	Establishes who supplies the fact
Data item	Exact series, count, or announcement	Same or revised item	Prevents comparing different measurements
Time window	Cutoff and time zone	Same or changed window	Can move observations in or out
Revision policy	Preliminary or final release	Different treatment	Determines whether corrections count
Fallback clause	Named alternate or process	Invoked or newly added	Tests whether substitution was authorized

Use original files where possible. If you must use screenshots, include the address bar, status, rule heading, and timestamp context. Keep a short note explaining how each file was obtained; do not annotate the only copy.

How can you tell whether a clarification is material?

A clarification is material when it could change which observations qualify, which authority controls, or which outcome wins. Ask a counterfactual question: applying the original text to the same public facts, could a reasonable reader reach a different eligible source or result than under the current text?

Changes to punctuation, formatting, a broken link, or an agency's renamed page may be non-material if the authority, dataset, field, time window, and decision rule remain identical. A new fallback source, new cutoff, different geographic unit, changed data revision, or replaced official body may be material even if the platform calls it a clarification.

Do not decide from the label alone. Document the actual before-and-after effect. The resolution-rules worksheet provides the fields needed for this comparison. If you did not save the rules before trading, look for official notices, downloadable terms, authenticated history, archives provided by the venue, or a cryptographic/onchain record rather than an unattributed repost.

Was the change authorized by the original contract?

Read the amendment, fallback, data-unavailability, obvious-error, and exceptional-circumstances clauses. A contract may expressly allow the venue to choose a named alternate source, correct an objective mistake, or clarify an ambiguity without changing the question's fundamental intent. Polymarket states that additional context can clarify resolution but cannot change the market's fundamental intent, and that such context is published through its resolution process.［3］ That rule belongs to Polymarket; another venue may use a different authority and process.

Check whether the required approver acted, whether the notice was published through the official channel, and whether it occurred before or after trading closed. Timing alone does not prove validity or invalidity, but it affects reliance and the dispute record. Also check whether the same policy was applied to all positions rather than only to one account.

If the original rule contains no applicable amendment or fallback power, ask support to cite the governing clause. Avoid broad accusations. A precise question—“Which clause authorized replacing source A with source B, and when was the notice published?”—is easier to answer and review.

How should you compare the two sources?

Confirm that both sources describe the same fact. Match the publisher, dataset or announcement, observation date, release date, time zone, unit, geography, inclusion rules, preliminary/final status, and correction policy. If one source reports a preliminary value and another a revised value, the disagreement may be about version timing rather than integrity.

Preserve the exact values that each source displayed at the contract cutoff. Do not cherry-pick a later revision unless the contract says later revisions count. If a source became unavailable, record the failure and the time; a temporary browser error does not establish permanent unavailability.

Kalshi's outcome guidance says that its contract terms identify the information and source used after expiry.［2］ That makes the named data and contract wording the relevant evidence, not which source seems more reputable in the abstract. The separate article on contract expiry explains where source collection sits in the lifecycle.

Kalshi's separate rules-summary guidance also treats the market-specific summary as a place to identify the criteria and verification source.［4］ Preserve the full contract as well as the summary because a short summary may omit amendment or fallback mechanics.

When should you file a formal dispute?

Use the formal channel when the source change appears material, lacks an identifiable authority, conflicts with the original rule, was applied inconsistently, or could alter the result. Follow the venue's deadline exactly. A long social-media thread does not preserve appeal rights.

Structure the submission around claims and evidence:

Identify the exact contract and disputed outcome.
Quote only the necessary original and current clauses.
List the version timestamps and official source records.
Explain the material difference in one neutral sentence.
Cite the amendment or fallback clause—or state that none was found.
Request a specific remedy: clarification, source history, review, or correction.

The guide to a disputed market result covers the later outcome challenge. This article is narrower: it builds the source-version record before or during that challenge.

What should you avoid while the result is pending?

Do not publish personal data, account identifiers, API credentials, or private support correspondence unnecessarily. Do not alter screenshots, rely on anonymous summaries as the only proof, or claim fraud merely because the change disadvantages your position. A financial incentive makes careful sourcing more important, not less.

Also avoid treating a changed source as an automatic void. The contract may authorize a fallback, continue to determine a result, enter dispute, or use an exceptional procedure. If the final notice says the contract was voided, use the separate voided-contract guide to evaluate that disposition.

Summary

Preserve the original contract, current contract, both source records, timestamps, and official notices.
Separate a display correction, clarification, authorized fallback, and material substitution.
Compare authority, dataset, cutoff, unit, revision policy, and outcome effect.
Ask which original clause authorized the change and who approved it.
File a concise, evidence-based dispute within the venue's deadline when the change is material.

Frequently Asked Questions

Can a prediction market change its resolution source?

It may do so only under its applicable rules and process. Some contracts define fallback or clarification powers, while others identify a source without the same flexibility.

Is fixing a broken source link a rule change?

Not necessarily. If the authority, dataset, field, time window, and revision policy remain the same, the link update may be administrative; preserve both versions to verify that conclusion.

Does a clarification after trading closes automatically invalidate the market?

No. Timing is relevant, but validity depends on the original authority, material effect, notice, and venue process. A clarification also should not silently rewrite the fundamental question.

What if I did not save the original rules?

Request the venue's official version history and look for authenticated notices, downloadable terms, or protocol records. Treat third-party screenshots as supporting evidence, not the sole source.

How do I prove the source change affected the outcome?

Apply the original and current rules to the same facts and show the differing eligible source, data field, cutoff, or result. Keep the explanation narrow and reproducible.

Should I contact the source agency directly?

You may verify its publication or correction policy, but the venue controls its contract process. Do not ask the agency to interpret a private platform rule unless that is part of its mandate.

Is a changed source the same as a disputed result?

No. A source-version question can exist before final resolution; a disputed result challenges a proposed or final outcome. The evidence can overlap, but the procedural stage differs.

Can a VPN restore the original resolution source?

No. Network routing does not control contract terms, source authority, amendments, or dispute decisions.

Disclaimer: This article provides general information, not financial, legal, tax, or trading advice. Resolution rules and dispute rights vary by venue, contract, and jurisdiction.

Sources:

Kalshi Help Center — Market Rules — https://help.kalshi.com/en/articles/13823822-market-rules
Kalshi Help Center — Market Outcomes — https://help.kalshi.com/en/articles/13823826-market-outcomes
Polymarket Documentation — Resolution — https://docs.polymarket.com/concepts/resolution
Kalshi Help Center — Rules Summary — https://help.kalshi.com/en/articles/13823823-rules-summary

Sources checked 12 September 2026.

Related reading:

Prediction Market Resolution Source Changed