Kleros, the Blockchain Dispute Resolution Layer that provides fast, secure and affordable arbitration for virtually everything. Kleros is hosted by the Thomson Reuters Incubator.

Federico Ast
Apr 25, 2018 · 6 min read

Today, millions of business, contractors and consumers depends on services that resolve payment disputes.

The ability to dispute past transactions due to fraud or disagreement is a proven necessity in e-commerce and contract work, resulting in trillions of dollars flowing through trusted intermediaries that provide dispute resolution services such as Visa and PayPal.

Yet no such service exists for cryptocurrencies. The inability to resolve a disputed transaction is one of crypto’s biggest barriers to growth.

What if anyone could use crypto with the same ease that we use existing payment and commerce solutions?

Kleros is a layer on top of Ethereum that provides fast, secure, and affordable arbitration. It uses crowdsourced arbitrators to offer a solution for disputed transactions in the crypto ecosystem.

Kleros will boost confidence in the crypto ecosystem and give a critical step to mass adoption.

The Problem Today

How do we settle disputes when transacting on a cross-border network without middle men? For example, Alice (who lives in France) wants to hire Bob (an app developer in Guatemala) to build an app.

They both worry that their counterparty might not honor the terms of the agreement. Existing dispute resolution methods (state courts and alternative dispute resolution systems) are too slow, too expensive or too complex to eliminate this risk.

The Future is Built on Kleros

Kleros — The justice protocol

Kleros provides fast, affordable, and transparent arbitration native to the decentralized internet. It is built for industries underserved by traditional arbitration and government court systems.


  • Escrow: To pay for an off-chain good or service, Kleros can be used to have the smart contract either reimburse the buyer or pay the seller.
  • Insurance: When an insured event happens, the insurer can validate it and compensate the insuree. If the insurer does not validate the event, a dispute resolution process would ensue. If the insuree wins the dispute resolution process, funds from the security deposit of the insurer would be transferred to the insuree.
  • Crowdfunding: Instead of backers sending funds to a wallet controlled by the project owners, they could send the payment to a Kleros controlled wallet. Funds would then be released as predefined milestones are met. Kleros would guarantee the fairness of the process.
  • Oracles: Oracles bridge the gap between the outside world and blockchains. Kleros can be used as an oracle in a number of critical applications such as insurance.
Kleros is hosted by the Thomson Reuters Incubator, a program that helps legaltech startups with expert executive mentorship and exploring partnership opportunities with TR products and business units. It’s an important step for Kleros to reach mass adoption.


We have signed two partnerships who will be early adopters of our decentralized dispute resolution services.

These partnerships will allow us to pilot test our technology in e-commerce disputes and token curated lists. These tests will prove that Kleros is ready for broad commercial use.

To keep up with future partnership announcements join our Kleros Announcement Telegram.


We launched Kleros’ Early Juror Program with the goal of recruiting early suppliers of adjudication services. The program included a small airdrop of 5 million PNK, (0.5% of the total supply), needed as a deposit to act as a juror.

All 5,000 available spots were filled in just 14 hours.

To learn more about Kleros’ Early Juror Program, read this post.

Token: Pinakion (PNK)

A Pinakion was the bronze plaque that each Athenian citizen in Ancient Greece used as an ID. It was often used as a token for jury selection in Athens’ popular trials.

PNK is a utility token. In order for a juror in the Kleros ecosystem to be elected to settle a specific dispute, he must deposit PNK. The more PNK deposited, the higher the likelihood of being selected. Jurors who don’t deposit any tokens cannot be selected to settle disputes.

PNK play two key functions in Kleros. First, it protects the system against the sybil attacks. Second, it incentivizes jurors to vote honestly by making incoherent jurors pay part of their deposit to coherent ones.

Bob, the loser in the dispute against Alice loses his 100$ deposit, which is used to pay arbitration fees to all jurors. Ignasi and Julio, the two jurors that voted incoherently with the rest, lose their PNK, which are transferred to the jurors who voted coherently. Daniel, Ezequiel, Frédéric, Gabriela and Hadass, the jurors who voted coherently, experience an economic gain in fees and tokens. Ignasi and Julio, the jurors who voted incoherently, earn arbitration fees but lose PNK.

Arbitration fees compensate jurors for their participation. All jurors ruling a case collect fees paid by the arbitrating parties(in ETH). Token redistribution creates the incentive for jurors to vote honestly by using a Schelling Point.

To learn more about the token economics, read the white paper.

MVP Preview

Both the dispute and juror sections of the product on Testnet.

Token Sale Deep Dive

Kleros token sale starts on May 15th and runs for 2 months till the 15th of July.

IICO Overview and Reasoning

The Interactive Coin Offering (IICO) is a new protocol advocated by Vitalik Buterin, Jason Teutsch and Christopher Brown to make token sales fair and low-risk. It lets each contributor choose an amount of ETH to bid and a “personal cap” on the total valuation.

As described in our Token Sale Strategy post, each Kleros token sale participant will indicate the amount of ETH he wants to contribute and the maximum valuation at which he is willing to participate.

The final valuation will be determined by the market, following a number of iterations where participants will make bids and adjust their caps. This provides certainty of participation and valuation to all parties, no matter their size.

Total token supply: 1,000,000,000 PNK

In the first token distribution event, 16% of tokens will be sold to the public. Buyers who purchase tokens early will receive a 20% bonus. The bonus decreases smoothly down to 10% at the beginning of the withdrawal lock period, and then goes to 0% by the end of the crowdsale.

Another 50% will be sold in the future as the team reaches milestones in project development and for juror incentive programs.

To learn more about how the Interactive Coin Offering works, see this post.

The sale is open to both US accredited investors and non-US buyers. Non accredited US nationals are not allowed to participate.

Token Distribution:

  • Team Members: 18.00%
  • First Round of Token Sale: 16.00%
  • Airdrop: 4.00%
  • Subsequent Rounds and Juror Incentive Programs: 50.00%
  • Kleros Cooperative Development Reserve: 12.00%

Founders and team members commit to work on the project for 3 years (from the time they started) or would have to reimburse a proportional part of their allocation (or everything if they leave before 1 year).

Expected Expenses of the Cooperative:

  • Product: 45.00%
  • R&D: 25.00%
  • Ecosystem: 10.00%
  • Communications: 10.00%
  • Operations: 05.00%
  • Legal: 05.00%

Kleros is incorporated as a French social enterprise, called a “cooperative company of public interest” or SCIC (sociétés coopératives d’intérêt collectif). This cooperative and community-oriented company operates under French jurisdiction and makes it possible to share the governance of the project.

This legal structure ensures that all funds of the cooperative will be used to develop the project. Founders cannot distribute funds of the cooperative under the form of dividends.

Learn more about Kleros legal structure here.

Project Roadmap and Timeline

Meet Kleros




  • William O’Rorke, Legal Advisor
  • Mitchell Loureiro, Token Sale Strategist, Artemis
  • Spencer Bramson, Community and Infrastructure Strategist, Artemis

Dig Deeper


If you’d like to support Kleros at this early stage, we are dedicating time to work with value adding parties to take Kleros to market.

Dr. Federico Ast , Co-Founder and CEO — federico@kleros.io

Clément Lesaege, Co-Founder and CTO — clement@kleros.io

Addison Huegel, PR — AHuegel@ElevatorPR.com


The Justice Protocol. A Dispute Resolution Layer for the decentralized age

Thanks to Stuart James, Clément Lesaege, and Spencer Bramson

Federico Ast

Written by

Ph.D. Entrepreneur. Blockchain & Law. Singularity University GSP16. TEDx Speaker. Coursera Teacher on Blockchain. Founder of Kleros.io.



The Justice Protocol. A Dispute Resolution Layer for the decentralized age

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