> ## 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.

# Appeals

> How to fund appeals in Kleros Court: asymmetric funding, appeal cost formulas, juror doubling, court jumps to parent courts, and appeal reward payouts.

The appeals system is a core feature of Kleros Court that ensures fairness and allows for error correction. Any party-or even third parties-can challenge a ruling by funding an appeal. [Read more here](https://blog.kleros.io/kleros-decentralized-token-listing-appeal-fees/)

<Note>
  Appeal mechanics are fundamentally the same in V1 and V2. The V2-specific enhancements (such as Dispute Kit jumps) are labeled where they appear below.
</Note>

***

## How Appeals Work

<Steps>
  <Step title="Initial Ruling">
    After jurors vote, a preliminary ruling is reached based on majority decision. This ruling enters the **Appeal Period**.
  </Step>

  <Step title="Appeal Funding">
    During the appeal period, anyone can fund an appeal:

    * **Challenger**: Funds to overturn the ruling (2× appeal cost)
    * **Winner**: Funds to defend the ruling (1× appeal cost)
  </Step>

  <Step title="Counter-Funding">
    If one side funds, the other side has the opportunity to counter-fund. If only one side funds fully, that side wins by default.
  </Step>

  <Step title="New Round">
    If both sides fund, a new round begins with more jurors. The process repeats until appeals are exhausted or unfunded.
  </Step>

  <Step title="Final Ruling">
    When no more appeals are funded (or the appeal period expires), the current ruling becomes final and is executed.
  </Step>
</Steps>

***

## Appeal Funding Requirements

The appeal system uses asymmetric funding to create proper incentives:

| Side                 | Funding Required | Rationale                                    |
| -------------------- | ---------------- | -------------------------------------------- |
| **Challenging Side** | 2× appeal cost   | Higher barrier discourages frivolous appeals |
| **Winning Side**     | 1× appeal cost   | Lower cost to defend legitimate rulings      |

### Calculating Appeal Cost

```
appealCost = feeForJuror × ((currentJurors × 2) + 1)
```

<Accordion title="Appeal Cost Example">
  **Scenario:** Current round has 3 jurors at 0.05 ETH each.

  Next round will have: (3 × 2) + 1 = **7 jurors**

  **Appeal costs:**

  * Challenger: 0.05 ETH × 7 × 2 = **0.70 ETH**
  * Winner: 0.05 ETH × 7 × 1 = **0.35 ETH**
</Accordion>

***

## Funding Deadlines

<Warning>
  Timing is critical for appeals. Miss the deadline and your opportunity is lost.
</Warning>

| Party          | Deadline                         |
| -------------- | -------------------------------- |
| **Challenger** | First half of appeal period only |
| **Winner**     | Entire appeal period             |

This asymmetry creates urgency for challengers while giving winners adequate time to respond.

***

## Juror Progression

With each appeal round, the number of jurors increases:

```
Round 1:  3 jurors
Round 2:  7 jurors    (3×2 + 1)
Round 3:  15 jurors   (7×2 + 1)
Round 4:  31 jurors   (15×2 + 1)
Round 5:  63 jurors   (31×2 + 1)
...
```

This exponential growth ensures that:

* Important cases receive thorough review
* The cost of repeated appeals increases substantially
* Eventually, a large enough jury reaches a stable consensus

***

## Court Jumps

When the number of jurors exceeds a threshold, the dispute "jumps" to a parent court:

### How Court Jumps Work

<Steps>
  <Step title="Threshold Reached">
    The dispute requires more jurors than the `jurorsForCourtJump` parameter (e.g., 511 jurors).
  </Step>

  <Step title="Escalation">
    The dispute automatically moves to the parent court in the hierarchy.
  </Step>

  <Step title="New Parameters">
    The dispute adopts the parent court's parameters and juror pool.
  </Step>

  <Step title="Continued Resolution">
    Jurors from the broader parent court now handle the case.
  </Step>
</Steps>

### V2 Enhancements

Kleros V2 introduces significant improvements to court jumps:

<CardGroup cols={2}>
  <Card title="Dispute Kit Jumps" icon="puzzle-piece">
    If a parent court doesn't support the current dispute kit, the dispute can switch to a compatible kit-including complex question types.
  </Card>

  <Card title="Dynamic Juror Adjustment" icon="sliders">
    Juror numbers adjust dynamically based on the new court's parameters and dispute kit requirements.
  </Card>
</CardGroup>

<Info>
  These jumps ensure that complex or contentious cases receive appropriate handling by a broader, less specialized jury.
</Info>

***

## Appeal Rewards

Successfully funding appeals can be profitable:

### If Your Side Wins

When you fund the winning side of an appeal:

* Your funding is returned
* You receive a portion of the losing side's funding as profit
* Rewards are proportional to your contribution

### If Your Side Loses

* Your funding is forfeited
* It's distributed to the winning side's funders

<Tip>
  Appeal funding is a form of crowdfunding justice. Multiple contributors can fund a side together, sharing in the rewards or losses proportionally.
</Tip>

***

## Strategic Considerations

### For Disputants

* **Evaluate Strength**: Only appeal if you have strong evidence the ruling was wrong
* **Consider Costs**: Each round is more expensive than the last
* **Time Your Funding**: Challengers must act in the first half of the appeal period

### For Third-Party Funders

* **Review Evidence**: Study the case before funding either side
* **Assess Probability**: Consider how likely the ruling is to change
* **Diversify Risk**: Fund multiple appeals to spread risk

### For Jurors

* **Expect Appeals**: Large-stake disputes often get appealed
* **Court Jumps**: You may be drawn for cases that jumped from sub-courts
* **Increased Complexity**: Appealed cases are often more contentious

***

## Appeal Flow Diagram

```
┌─────────────────────────────────────────────────────────────┐
│                     INITIAL RULING                          │
│                    (3 jurors vote)                          │
└─────────────────────────┬───────────────────────────────────┘
                          │
                          ▼
┌─────────────────────────────────────────────────────────────┐
│                     APPEAL PERIOD                           │
│   Challenger funds (2×) ◄──────► Winner funds (1×)          │
└─────────────────────────┬───────────────────────────────────┘
                          │
            ┌─────────────┼─────────────┐
            │             │             │
            ▼             ▼             ▼
     ┌──────────┐  ┌──────────┐  ┌──────────┐
     │  Both    │  │  Only    │  │ Neither  │
     │  Fund    │  │ One Funds│  │  Funds   │
     └────┬─────┘  └────┬─────┘  └────┬─────┘
          │             │             │
          ▼             ▼             ▼
     ┌──────────┐  ┌──────────┐  ┌──────────┐
     │  NEW     │  │ Funded   │  │ Current  │
     │  ROUND   │  │ Side     │  │ Ruling   │
     │(7 jurors)│  │  Wins    │  │ Executed │
     └──────────┘  └──────────┘  └──────────┘
```

***

## What's Next?

<CardGroup cols={3}>
  <Card title="Court Hierarchy" icon="sitemap" href="/court/court-hierarchy">
    Understand how courts are organized
  </Card>

  <Card title="How It Works" icon="cogs" href="/court/how-it-works">
    Full dispute resolution process
  </Card>

  <Card title="Fund an Appeal" icon="hand-holding-dollar" href="https://court.kleros.io">
    Browse active cases with open appeals
  </Card>
</CardGroup>

***

## Quick Links

<CardGroup cols={2}>
  <Card title="Appeal Calculator" icon="calculator" href="https://v2.kleros.builders/">
    Estimate appeal costs for active disputes
  </Card>

  <Card title="Active Appeals" icon="gavel" href="https://v2.kleros.builders/">
    View disputes currently in appeal period
  </Card>
</CardGroup>