> ## Documentation Index
> Fetch the complete documentation index at: https://kleros-mintlify-6ebc7975.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Overview

> Kleros Court is a decentralized arbitration protocol using random jurors, PNK staking, and crypto-economic incentives on Ethereum (V1) and Arbitrum (V2).

<Frame>
  <img src="https://mintcdn.com/kleros-mintlify-6ebc7975/6i-2aJXQiPgBJ2TJ/images/court-hero.png?fit=max&auto=format&n=6i-2aJXQiPgBJ2TJ&q=85&s=d2fbd08a8a1deca40157640d726b23e4" alt="Kleros Court Interface" width="2992" height="1700" data-path="images/court-hero.png" />
</Frame>

# Kleros Court

**Kleros Court** is a decentralized dispute resolution protocol that provides arbitration services for smart contracts and decentralized applications. It works by randomly selecting jurors from a pool who are incentivized to resolve disputes honestly through a crypto-economic mechanism based on game theory.

Think of it as a decentralized judiciary for Web3. When a dispute arises, jurors are randomly drawn, they review evidence, vote on the outcome, and the majority decision is enforced-all without centralized intermediaries.

Kleros Court comes in two versions. **V1** is the production-proven protocol running on Ethereum since 2018. **V2** is the next-generation upgrade on Arbitrum with a modular architecture.

***

## V1 - Production Protocol

Court V1 launched on Ethereum Mainnet in 2018 and has resolved over 1,500 disputes. Its core smart contract is **KlerosLiquid**, a single (monolithic) contract that combines juror staking, random selection, voting, and dispute management.

<Frame>
  <img src="https://mintcdn.com/kleros-mintlify-6ebc7975/6i-2aJXQiPgBJ2TJ/images/v1-court.png?fit=max&auto=format&n=6i-2aJXQiPgBJ2TJ&q=85&s=16ff21577420fb655b3f8190a0b0ca75" alt="Court V1 interface, screenshot to be added" width="2944" height="1716" data-path="images/v1-court.png" />
</Frame>

| Aspect            | Court V1                                                  |
| ----------------- | --------------------------------------------------------- |
| **Network**       | Ethereum L1 (also Gnosis Chain)                           |
| **Core contract** | KlerosLiquid (monolithic)                                 |
| **Standards**     | ERC-792 (arbitration), ERC-1497 (evidence)                |
| **Staking**       | PNK stays in the juror's wallet                           |
| **Voting**        | Commit-reveal with plurality aggregation                  |
| **RNG**           | Blockhash-based                                           |
| **Courts**        | Hierarchical subcourt tree with the General Court as root |

Jurors stake PNK directly from their wallet in a subcourt, are drawn at random with probability proportional to their stake, then commit and reveal their votes on the submitted evidence. Coherent jurors are rewarded; incoherent jurors lose part of their stake.

***

## V2 - Next-Gen Upgrade

Court V2 runs on Arbitrum L2 and replaces the monolithic contract with a modular design: **KlerosCore** coordinates disputes, the **SortitionModule** handles juror selection, and pluggable **DisputeKits** provide the resolution mechanism. Cross-chain disputes are relayed through the **VEA bridge**.

***

## Key Capabilities

<CardGroup cols={2}>
  <Card title="Random Juror Selection" icon="shuffle">
    Jurors are randomly drawn from stakers, weighted by their PNK stake
  </Card>

  <Card title="Crypto-Economic Incentives" icon="coins">
    Honest voting is rewarded; incoherent votes result in stake slashing
  </Card>

  <Card title="Hierarchical Courts" icon="sitemap">
    Specialized courts for different dispute types with appeals to parent courts
  </Card>

  <Card title="Modular Dispute Kits" icon="puzzle-piece">
    Pluggable resolution mechanisms: Classic, Shutter (encrypted), Gated (SBT-eligibility), and GatedShutter
  </Card>

  <Card title="Cross-Chain Support" icon="link">
    Disputes from any EVM chain resolved on Arbitrum via Vea bridge
  </Card>

  <Card title="Trustless Execution" icon="shield-check">
    Rulings are enforced automatically by smart contracts
  </Card>
</CardGroup>

***

## How It Works

At its core, Kleros works through a simple yet powerful process:

<Steps>
  <Step title="Dispute Creation">
    An application encounters a contentious situation and creates a dispute in Kleros, paying arbitration fees.
  </Step>

  <Step title="Juror Selection">
    Jurors are randomly drawn from those who have staked PNK in the relevant court. Selection probability is proportional to stake.
  </Step>

  <Step title="Evidence & Voting">
    Jurors review evidence submitted by both parties and cast their votes during the voting period.
  </Step>

  <Step title="Resolution">
    The majority decision is enforced. Coherent jurors are rewarded; incoherent jurors lose a portion of their stake.
  </Step>
</Steps>

### The Incentive Structure

The system is designed so **you don't need to trust anyone**:

* **Jurors** are incentivized to vote honestly (or lose their staked PNK)
* **Disputants** pay fees only for resolution, with no protocol commission
* **Appellants** can challenge rulings by funding additional rounds

This creates a self-policing system where dishonest behavior is economically punished.

***

## Core Components

| Component            | Purpose                                                                     |
| -------------------- | --------------------------------------------------------------------------- |
| **KlerosCore**       | The main arbitrator contract that coordinates disputes and enforces rulings |
| **Sortition Module** | Handles juror selection using a three-phase system to prevent manipulation  |
| **Dispute Kits**     | Modular resolution mechanisms (Classic, Shutter, Ranked Choice, etc.)       |
| **Vea Bridge**       | Enables cross-chain dispute resolution from foreign chains                  |

***

## Who Uses Kleros Court?

* **DeFi Protocols** resolve oracle disputes, liquidation challenges, and governance conflicts
* **Prediction Markets** settle market outcomes with decentralized arbitration
* **Escrow Services** release funds based on impartial third-party rulings
* **DAOs** handle contributor disputes and proposal challenges
* **Insurance Protocols** adjudicate claims without centralized authority
* **NFT Marketplaces** resolve authenticity and ownership disputes

***

## What Changed in V2

V2 keeps the same crypto-economic model as V1 and changes how it is implemented and where it runs:

| Component              | V1                        | V2                                                            |
| ---------------------- | ------------------------- | ------------------------------------------------------------- |
| **Network**            | Ethereum L1               | Arbitrum L2                                                   |
| **Core contract**      | KlerosLiquid (monolithic) | KlerosCore (modular)                                          |
| **Juror selection**    | Built into KlerosLiquid   | SortitionModule (separate)                                    |
| **Dispute resolution** | Single mechanism          | Pluggable DisputeKits (Classic, Shutter, Gated, GatedShutter) |
| **Cross-chain**        | Single chain              | Multi-chain via VEA bridge                                    |
| **Staking**            | PNK stays in wallet       | PNK transfers to contract                                     |
| **RNG**                | Single source             | Enhanced with fallback mechanisms                             |

<Note>
  Kleros V2 is currently in beta with 100+ disputes successfully processed. The system is undergoing internal review and external audits.
</Note>

***

## Current Status

As of the May 2026 development update:

* **Court V2**: the partial-coherence dispute kit was merged, and contract simplification across dispute kits was merged (June 2026).
* **Court V1**: April staking rewards were shipped in the rewards exporter.

Follow development on the [Kleros blog - developer updates](https://blog.kleros.io/tag/developer/).

***

## What's Next?

<CardGroup cols={3}>
  <Card title="How It Works" icon="cogs" href="/court/how-it-works">
    Deep dive into the dispute resolution process
  </Card>

  <Card title="Court Hierarchy" icon="sitemap" href="/court/court-hierarchy">
    Understand the court structure and specialization
  </Card>

  <Card title="Appeals" icon="scale-balanced" href="/court/appeals">
    Learn how appeals and escalation work
  </Card>

  <Card title="V2 Architecture" icon="layer-group" href="/court/architecture">
    Design principles, multi-chain vision, and security model
  </Card>
</CardGroup>

***

## Quick Links

<CardGroup cols={2}>
  <Card title="Launch Court" icon="rocket" href="https://v2.kleros.builders">
    Open the Kleros Court application
  </Card>

  <Card title="Become a Juror" icon="user-plus" href="/tutorials/juror-tutorial-v1">
    Step-by-step staking and voting tutorial
  </Card>

  <Card title="Contract Addresses" icon="file-contract" href="/reference/contracts/deployment-addresses">
    Court V2 deployment addresses
  </Card>

  <Card title="Kleros SDK" icon="code" href="/reference/sdk/kleros-sdk">
    Integrate Kleros into your application
  </Card>
</CardGroup>