The Verification Team

In the How Do Markets Resolve? chapter, we learned that for a Polymarket to resolve, someone must submit a proposed outcome. If that proposal goes unchallenged for two hours, the market resolves to the proposed answer. If the proposal is challenged, it enters a discussion phase followed by a vote, where UMA oracle participants decide the final outcome.

In Basics, we reviewed the key stakeholders involved in this resolution process: proposers, disputers, and oracle participants. This case study explores a lesser-known type of participant: verifiers.

Who are Verifiers?

Verifiers are users who review proposed outcomes after a market closes, ensuring that the submitted answer aligns with the actual result and the market's resolution criteria. They operate during the critical two-hour window between when a proposal is submitted and when it finalizes.

While proposers submit answers and disputers challenge incorrect ones, verifiers handle everything in between. They validate claims, check sources, raise doubts, and issue alerts when necessary.

Additionally, most proposals and disputes are submitted by bots, not individuals. This makes human verification especially important. Verifiers can catch what bots often miss, particularly in edge cases, ambiguous markets, or situations where judgment and context matter.

Oracle Participants

Before we continue, let's take a moment to review the main roles in the oracle process:

• Proposer: Submits the outcome and stakes a bond.

• Disputer: Challenges the proposal by staking an equal bond.

• Verifier: Reviews proposals for accuracy and decides whether a dispute should be initiated.

• Community Member: Discusses proposals, disputes, and market resolution.

• Voter: Participates in determining the final outcome via voting.

What Does This Matter?

The Verification Team has been at the center of several controversies, particularly in the first half of 2025. Incidents like the Astros vs. Dodgers misresolution have drawn increasing criticism from the community. More recently, concerns have escalated around the team’s growing error rate, lack of due diligence, and questionable actions such as controversial dispute alerts.

In this case study, we'll take a deep dive into the Verification Team: how they operate, their incentives and challenges, the criticisms they've faced, and how the system might move forward from here.

Coming Up

In the next chapter, we begin the case study by learning what verification entails.